Image processing apparatus, image processing method and manufacturing apparatus

ABSTRACT

An image processing apparatus having a plurality of Bayer arrays each including 4 pixels sharing a common electrode connected to a vertical signal line wherein: each of the pixels has a pixel electrode connected to a horizontal signal line; and the location of each of the horizontal signal lines and the location of each of the pixel electrodes each connected to one of the horizontal signal lines are determined so that the locations in a neighboring Bayer array are a mirror image of counterpart locations in another Bayer array adjacent to the neighboring Bayer array.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/101,129, filed Aug. 10, 2018, now U.S. Pat. No. 10,277,857, which isa continuation of U.S. patent application Ser. No. 15/647,072, filedJul. 11, 2017, now U.S. Pat. No. 10,070,091, which is a continuation ofU.S. patent application Ser. No. 15/612,637, filed Jun. 2, 2017, nowU.S. Pat. No. 9,888,201, which is a continuation of U.S. patentapplication Ser. No. 14/045,650, filed Oct. 3, 2013, now U.S. Pat. No.9,001,239, which is a continuation of U.S. patent application Ser. No.12/487,149, filed Jun. 18, 2009, now U.S. Pat. No. 8,576,311, whichclaims priority to Japanese Patent Application Serial No. JP2008-161273, filed in the Japan Patent Office on Jun. 20, 2008, theentire disclosures of which are hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

In general, the present invention relates to an image processingapparatus, an image processing method and a device manufacturingapparatus. More particularly, the present invention relates to an imageprocessing apparatus which is capable of improving sensitivitydeteriorations caused by the increasing number of pixels created on thedisplay screen of the apparatus as pixels each having a small size andcapable of increasing a speed when video is recording. The presentinvention also relates to an image processing method adopted by theimage processing apparatus and relates to a manufacturing apparatus formanufacturing the image processing apparatus.

2. Description of the Related Art

Image taking apparatus such as a video camera include an apparatus whichis capable of taking not only a moving image but also a static image. Inan image taking apparatus provided with both a moving-image taking modefor taking a moving image and a static-image taking mode for taking astatic image, when an image is taken in the static-image taking mode,signals are read out from all pixels provided on the display screen.When an image is taken in the moving-image taking mode, on the otherhand, data is read out from predetermined pixels provided on the displayscreen in the so-called thinned-out read operation.

When an image is taken in the moving-image taking mode, the imageprocessing apparatus adopts a frame-rate increasing method by which thethinned-out read operation is carried out, undesirably sacrificing pixelinformation displayed on the screen to a certain degree. Technologiesunderlying the method for increasing the frame rate are studied. Thetechnologies include a technology underlying a method for increasing thespeed at which pixel signals are read out and for carrying out thethinned-out read operation by devising the layout of wires and imagetaking devices. The technologies also include a technology underlying amethod for optimally adjusting the sensitivity and the dynamic range.

Japanese Patent Laid-open No. 2006-319407 (hereinafter referred to asPatent Document 1) discloses an image taking apparatus which is switchedfrom an all-pixel read mode to a thinned-out read mode and vice versa.Patent Document 1 shows the configuration of an image taking apparatuslike one shown in a diagram of FIG. 1.

To put it in detail, the FIG. 1 is a circuit diagram showing R (Red)pixels, G (Green) pixels and B (Blue) pixels placed along the first tofourth rows and along the first and sixteenth columns. The figure alsoshows states of connections between the pixels and a first horizontalsignal line group 15D and between the pixels and a second horizontalsignal line group 15U. It is to be noted that, even though the followingdescription explains only R (Red) pixels, G (Green) pixels and B (Blue)pixels placed along the first to fourth rows and along the first andsixteenth columns, the configurations of R (Red) pixels, G (Green)pixels and B (Blue) pixels placed along other rows and along othercolumns are the same as the pixels explained in the followingdescription.

The first horizontal signal line group 15D is configured to include fourhorizontal signal lines, i. e., horizontal signal lines 15D1 to 15D4. Bythe same token, the second horizontal signal line group 15U isconfigured to include four horizontal signal lines, i. e., horizontalsignal lines 15U1 to 15U4.

An R pixel 20 (1, 1) is placed at the intersection of the first row andthe first column whereas a G pixel 20 (1, 2) is placed at theintersection of the first row and the second column. In this way, at theintersections of the first row and the third to sixteenth columns, R andG pixels are arranged alternately. By the same token, an R pixel 20 (3,1) is placed at the intersection of the third row and the first columnwhereas a G pixel 20 (3, 2) is placed at the intersection of the thirdrow and the second column. In this way, at the intersections of thethird row and the third to sixteenth columns, R and G pixels arearranged alternately.

A G pixel 20 (2, 1) is placed at the intersection of the second row andthe first column whereas a B pixel 20 (2, 2) is placed at theintersection of the second row and the second column. In this way, atthe intersections of the second row and the third to sixteenth columns,G and B pixels are arranged alternately. By the same token, a G pixel 20(4, 1) is placed at the intersection of the fourth row and the firstcolumn whereas a B pixel 20 (4, 2) is placed at the intersection of thefourth row and the second column. In this way, at the intersections ofthe fourth row and the third to sixteenth columns, G and B pixels arearranged alternately.

The first vertical signal line 17D (1) laid along the first column isconnected to the R pixel 20 (1, 1) placed at the intersection of thefirst row and the first column as well as the R pixel 20 (3, 1) placedat the intersection of the third row and the first column. By the sametoken, any odd-numbered first vertical signal line 17D laid along anodd-numbered column is connected to the R pixel placed at theintersection of the first row and the odd-numbered column as well as theR pixel placed at the intersection of the third row and the odd-numberedcolumn. For example, the first vertical signal line 17D (15) laid alongthe fifteenth column is connected to the R pixel 20 (1, 15) placed atthe intersection of the first row and the fifteenth column as well asthe R pixel 20 (3, 15) placed at the intersection of the third row andthe fifteenth column.

The second vertical signal line 17U (1) laid along the first column isconnected to the G pixel 20 (2, 1) placed at the intersection of thesecond row and the first column as well as the G pixel 20 (4, 1) placedat the intersection of the fourth row and the first column. By the sametoken, any odd-numbered second vertical signal line 17U laid along anodd-numbered column is connected to the G pixel placed at theintersection of the second row and the odd-numbered column as well asthe G pixel placed at the intersection of the fourth row and theodd-numbered column. For example, the second vertical signal line 17U(15) laid along the fifteenth column is connected to the G pixel 20 (2,15) placed at the intersection of the second row and the fifteenthcolumn as well as the G pixel 20 (4, 15) placed at the intersection ofthe fourth row and the fifteenth column.

The first vertical signal line 17D (2) laid along the second column isconnected to the B pixel 20 (2, 2) placed at the intersection of thesecond row and the second column as well as the B pixel 20 (4, 2) placedat the intersection of the fourth row and the second column. By the sametoken, any even-numbered first vertical signal line 17D laid along aneven-numbered column is connected to the B pixel placed at theintersection of the second row and the even-numbered column as well asthe B pixel placed at the intersection of the fourth row and theeven-numbered column. For example, the first vertical signal line 17D(16) laid along the sixteenth column is connected to the B pixel 20 (2,16) placed at the intersection of the second row and the sixteenthcolumn as well as the B pixel 20 (4, 16) placed at the intersection ofthe fourth row and the sixteenth column.

The second vertical signal line 17U (2) laid along the second column isconnected to the G pixel 20 (1, 2) placed at the intersection of thefirst row and the second column as well as the G pixel 20 (3, 2) placedat the intersection of the third row and the second column. By the sametoken, any even-numbered second vertical signal line 17U laid along aneven-numbered column is connected to the G pixel placed at theintersection of the first row and the even-numbered column as well asthe G pixel placed at the intersection of the third row and theeven-numbered column. For example, the second vertical signal line 17U(16) laid along the sixteenth column is connected to the G pixel 20 (1,16) placed at the intersection of the first row and the sixteenth columnas well as the G pixel 20 (3, 16) placed at the intersection of thethird row and the sixteenth column.

The first vertical signal lines 17D (1), 17D (2), 17D (15) and 17D (16)laid along the first, second, fifteenth and sixteenth columnsrespectively are connected to a horizontal signal line 15D1. The firstvertical signal lines 17D (3), 17D (4), 17D (13) and 17D (14) laid alongthe third, fourth, thirteenth and fourteenth columns respectively areconnected to a horizontal signal line 15D2. The first vertical signallines 17D (5), 17D (6), 17D (11) and 17D (12) laid along the fifth,sixth, eleventh and twelfth columns respectively are connected to ahorizontal signal line 15D3. The first vertical signal lines 17D (7),17D (8), 17D (9) and 17D (10) laid along the seventh, eighth, ninth andtenth columns respectively are connected to a horizontal signal line15D4.

It is to be noted that the first vertical signal lines 17D (1) to 17D(16) provided for the columns are connected to the horizontal signallines 15D1 to 15D4 by a CDS (Correlated Double Sampling)/SH (SampleHold) circuit and column select switches. However, the CDS/SH circuitand the column select switches are not shown in the diagram of FIG. 1.

The second vertical signal lines 17U (1), 17U (2), 17U (15) and 17U (16)laid along the first, second, fifteenth and sixteenth columnsrespectively are connected to a horizontal signal line 15U1. The secondvertical signal lines 17U (3), 17U (4), 17U (13) and 17U (14) laid alongthe third, fourth, thirteenth and fourteenth columns respectively areconnected to a horizontal signal line 15U2. The second vertical signallines 17U (5), 17U (6), 17U (11) and 17U (12) laid along the fifth,sixth, eleventh and twelfth columns respectively are connected to ahorizontal signal line 15U3. The second vertical signal lines 17U (7),17U (8), 17U (9) and 17U (10) laid along the seventh, eighth, ninth andtenth columns respectively are connected to a horizontal signal line15U4.

It is to be noted that the second vertical signal lines 17U (1) to 17U(16) provided for the columns are connected to the horizontal signallines 15U1 to 15U4 by a CDS/SH circuit and column select switches.However, the CDS/SH circuit and the column select switches are not shownin the diagram of FIG. 1.

In each of portions above and below a pixel area of the Bayer array CMOS(Complementary Metal Oxide Semiconductor) image sensor adopting a columnCDS method as is the case with one shown in the diagram of FIG. 1, aCDS/SH processing section, a column select switch sections and fourhorizontal signal lines are provided. If necessary, each of the columnselect portions is switched to select columns. By switching the columnselect portions, the read operation can be carried out in each of anall-pixel read mode, a ½ thinned-out read mode and ¼ thinned-out readmode. That is to say, output processing can be carried out in athinned-out read mode.

The configuration of another existing image taking apparatus isexplained by referring to a diagram of FIG. 2. Much like the imagesensor employed in the existing image taking apparatus shown in thediagram of FIG. 1, an image sensor 50 employed in the other existingimage taking apparatus shown in the diagram of FIG. 2 is a CMOS imagesensor of a column CDS Bayer array system. The image sensor 50 employedin the other existing image taking apparatus shown in the diagram ofFIG. 2 is described in Japanese Patent Laid-open No. 2007-124137. Theimage sensor 50 shown in the diagram of FIG. 2 employs a pixel arraysection 51, left and right V decoders (or vertical scan circuits) 52-1and 52-2, upper and lower H decoders (or horizontal scan circuits) 53-1and 53-2, upper and lower CDS circuits 54-1 and 54-2, upper and lowerhorizontal select transistors 55-1 and 55-2, upper and lower horizontalsignal lines 56-1 and 56-2, vertical signal lines 57-1 and 57-2 as wellas vertical select lines 58-1 and 58-2.

The pixel array section 51 has a first pixel group composed of aplurality of pixels 59-1 laid out 2-dimensionally to form a pixel matrixand a second pixel group composed of a plurality of pixels 59-2 laid out2-dimensionally to form a pixel matrix. Each of the pixels 59-1 and 59-2employed in the pixel array section 51 has the configuration of arectangular pixel employed in the image sensor shown in the diagram ofFIG. 1 except that the pixels 59-1 and 59-2 are laid out in an inclineddirection forming an angle of 45 degrees in conjunction with thevertical or horizontal direction. In this layout, pixels arranged on anyspecific pixel row are separated away from pixels arranged on a rowadjacent to the specific pixel row by a distance equal to half the sizeof a pixel. By the same token, pixels arranged on any specific pixelcolumn are separated away from pixels arranged on a column adjacent tothe specific pixel column by a distance equal to half the size of apixel. That is to say, the pixels 59-1 composing the first pixel groupare separated away from the pixels 59-2 composing the second pixel groupin both the horizontal and vertical directions by a distance equal tohalf the size of a pixel. Each of the pixels 59-1 and 59-2 includes apixel circuit, and a color filter is set for each of the pixels 59-1 and59-2.

A color matrix of a Bayer array is created on each of the first andsecond pixel group. The Bayer array has a typical 2×2 RGBGconfiguration. In the sequence RGBG, notation R denotes a red-colorfilter, notation G denotes a green-color filter and notation B denotes ablue-color filter. In the image sensor 50 shown in the diagram of FIG.2, the Bayer array on the first pixel group is referred to as Bayerarray 1 whereas the Bayer array on the second pixel group is referred toas Bayer array 2.

As shown in the diagram of FIG. 2, the 2×2 color matrix of the firstpixel group overlaps the 2×2 color matrix of the second pixel group. TheV decoder 52-1 selects pixels 59-1 of the first pixel group in the pixelarray section 51 through the vertical select line 58-1 in row units. Theselection process is carried out sequentially on a row-after-row basisstarting from the bottom end, and pixel signals are read outsimultaneously as a batch from each row. The CDS circuit 54-1 carriesout a correlation double sampling process on the pixel signals, whichare read out from the first pixel group of the pixel array section 51 inrow units, in order to reduce reset noises.

In this case, an electric potential of a 0-level period following areset period of the pixel signal is clamped to an electric potentialdetermined in advance by making use of a clamp pulse. Then, a signalperiod of the pixel signal is sampled and held by making use of asample-hold pulse S/H (Sample/Hold) in order to obtain a pixel signalhaving fewer reset noises. The H decoder 53-1 selects a pixel signalfrom pixel signals output by the CDS circuit 54-1 for 1 rowsequentially, starting from the left end on a pixel-after-pixel basis.The transistor 55-1 for horizontal selection serves as a horizontaloutput circuit. In this case, a transistor 55-1 provided at a locationselected by the H decoder 53-1 is put in a turned-on state, outputtingthe pixel signal sampled and held by the CDS circuit 54-1 to thehorizontal signal line 56-1. The pixel signals sequentially output tothe horizontal signal line 56-1 in this way form a first image signalHL1.

The first image signal HL1 obtained from the first pixel group isamplified by a later-stage amplifier not shown in the diagram of FIG. 2and is then output to a recipient outside the image sensor. In addition,the V decoder 52-2 selects pixels 59-2 of the second pixel group of thepixel array section 51 through the vertical select line 58-2 in rowunits. The selection process is carried out sequentially on arow-after-row basis starting from the bottom end, and pixel signals areread out simultaneously as a batch from each row. The CDS circuit 54-2carries out a correlation double sampling process on the pixel signals,which are read out from the second pixel group of the pixel arraysection 51 in row units, in order to reduce reset noises. The H decoder53-2 selects a pixel signal from pixel signals output by the CDS circuit54-2 for 1 row sequentially, starting from the left end on apixel-after-pixel basis.

The transistor 55-2 for horizontal selection serves as a horizontaloutput circuit. In this case, a transistor 55-2 provided at a locationselected by the H decoder 53-2 is put in a turned-on state, outputtingthe pixel signal sample-held by the CDS circuit 54-2 to the horizontalsignal line 56-2. The pixel signals sequentially output to thehorizontal signal line 56-2 in this way form a second image signal HL2.The second image signal HL2 obtained from the second pixel group isamplified by a later-stage amplifier not shown in the diagram of FIG. 2and is then output to a recipient outside the image sensor.

Next, the pixel circuit of every pixel 59-1 and every pixel 59-2 isexplained. FIG. 3 is a diagram showing the pixel circuits. Each of thepixel circuits is configured to employ a photodiode PD, a transfertransistor T1, a reset transistor T2, an amplification transistor T3 anda select transistor T4. The photodiode PD is an element provided with anopto-electrical conversion function and an electrical-chargeaccumulation function. The anode of the photodiode PD is connected tothe ground. The photodiode PD carries out a conversion process toconvert incident light into an electrical charge having a magnituderepresenting the quantity of the light and accumulates the electricalcharge obtained as a result of the conversion process. The transfertransistor T1 is connected between the cathode of the photodiode PD anda floating diffusion section FD. The transfer transistor T1 transfersthe electrical charge generated by the photodiode PD to the floatingdiffusion section FD with a timing determined by a transfer pulse TRSapplied to the gate of the transfer transistor T1.

The reset transistor T2 is connected between a power supply and thefloating diffusion section FD. The reset transistor T2 resets theelectric potential of the floating diffusion section FD to the electricpotential of the power supply with a timing determined by a reset pulseRST applied to the gate of the reset transistor T2. The floatingdiffusion section FD is also connected to the gate of the amplificationtransistor T3. The amplification transistor T3 is connected to thevertical signal lines 57-1 and 57-2 by the select transistor T4. Whenthe select transistor T4 is put in a turned-on state on the basis of apixel select signal SEL, the amplification transistor T3 asserts avoltage according to an electric potential, which is obtained as aresult of amplifying the electric potential appearing on the floatingdiffusion section FD, on the vertical signal lines 57-1 and 57-2.

The image sensor 50 shown in the diagram of FIG. 2 has pixels of thefirst and second pixel groups separated from each other in both thehorizontal and vertical directions by a distance equal to half the sizeof a pixel. The image sensor 50 executes control so that theelectrical-charge accumulation time for the first pixel group isdifferent from the electrical-charge accumulation time for the secondpixel group. Then, image signals obtained from the first and secondpixel groups are synthesized to produce an output image signal. As aresult, it is possible to easily obtain sensitivity and a dynamic rangewhich are optimum for the image.

SUMMARY OF THE INVENTION

In recent years, the size of a video camera has been becoming smallerand smaller. In addition, an image sensor is mounted in a cellular phonebesides image taking apparatus such as a video camera. In suchapplications, an image sensor having a small size is also desirable. Ifthe size of the image sensor is reduced, however, the dimensions ofevery pixel employed in the image sensor must also be decreased. As aresult, it is quite within the bounds of possibility that thesensitivity of the image sensor deteriorates. In addition, it is alsoquite within the bounds of possibility that the processing speed canhardly be raised if the thinned-out operation described previously iscarried out to take a moving image.

In order to solve the problems described above, in the Bayer array, theimage sensor having a shared pixel structure is provided with a portionshown in a diagram of FIG. 3. FIG. 4 is a diagram showing the circuit ofthe image sensor shown in FIG. 3. In the image sensor shown in thediagrams of FIGS. 3 and 4, an R pixel 100 (1, 1), a G pixel 100 (1, 2),a G pixel 100 (2, 1) and a B pixel 100 (2, 2) compose a Bayer array101-1. The Bayer array 101-1 is provided with a common electrode 102-1to serve as a shared electrode common to the R pixel 100 (1, 1), the Gpixel 100 (1, 2), the G pixel 100 (2, 1) and the B pixel 100 (2, 2). Thecommon electrode 102-1 is connected to a vertical signal line 103-1.

By the same token, an R pixel 100 (1, 3), a G pixel 100 (1, 4), a Gpixel 100 (2, 3) and a B pixel 100 (2, 4) compose a Bayer array 101-2.The Bayer array 101-2 is provided with a common electrode 102-2 to serveas a shared electrode common to the R pixel 100 (1, 3), the G pixel 100(1, 4), the G pixel 100 (2, 3) and the B pixel 100 (2, 4). The commonelectrode 102-2 is connected to a vertical signal line 103-2.

In the same way, an R pixel 100 (1, 5), a G pixel 100 (1, 6), a G pixel100 (2, 5) and a B pixel 100 (2, 6) compose a Bayer array 101-3. TheBayer array 101-3 is provided with a common electrode 102-3 to serve asa shared electrode common to the R pixel 100 (1, 5), the G pixel 100 (1,6), the G pixel 100 (2, 5) and the B pixel 100 (2, 6). The commonelectrode 102-3 is connected to a vertical signal line 103-3.

Likewise, an R pixel 100 (1, 7), a G pixel 100 (1, 8), a G pixel 100 (2,7) and a B pixel 100 (2, 8) compose a Bayer array 101-4. The Bayer array101-4 is provided with a common electrode 102-4 to serve as a sharedelectrode common to the R pixel 100 (1, 7), the G pixel 100 (1, 8), theG pixel 100 (2, 7) and the B pixel 100 (2, 8). The common electrode102-4 is connected to a vertical signal line 103-4.

In addition, every pixel 100 is provided with a pixel electrodeconnected to one of the horizontal signal lines 104-1 to 104-4. To putit more concretely, the R pixel 100 (1, 1) is provided with a pixelelectrode 105-1 connected to the horizontal signal line 104-1 whereasthe G pixel 100 (1, 2) is provided with a pixel electrode 105-2connected to the horizontal signal line 104-2. On the other hand, the Rpixel 100 (1, 3) is provided with a pixel electrode 105-3 connected tothe horizontal signal line 104-1 whereas the G pixel 100 (1, 4) isprovided with a pixel electrode 105-4 connected to the horizontal signalline 104-2.

In addition, the R pixel 100 (1, 5) is provided with a pixel electrode105-5 connected to the horizontal signal line 104-1 whereas the G pixel100 (1, 6) is provided with a pixel electrode 105-6 connected to thehorizontal signal line 104-2. On the other hand, the R pixel 100 (1, 7)is provided with a pixel electrode 105-7 connected to the horizontalsignal line 104-1 whereas the G pixel 100 (1, 8) is provided with apixel electrode 105-8 connected to the horizontal signal line 104-2.

On top of that, the G pixel 100 (2, 1) is provided with a pixelelectrode 106-1 connected to the horizontal signal line 104-3 whereasthe B pixel 100 (2, 2) is provided with a pixel electrode 106-2connected to the horizontal signal line 104-4. On the other hand, the Gpixel 100 (2, 3) is provided with a pixel electrode 106-3 connected tothe horizontal signal line 104-3 whereas the B pixel 100 (2, 4) isprovided with a pixel electrode 106-4 connected to the horizontal signalline 104-4.

In addition, the G pixel 100 (2, 5) is provided with a pixel electrode106-5 connected to the horizontal signal line 104-3 whereas the B pixel100 (2, 6) is provided with a pixel electrode 106-6 connected to thehorizontal signal line 104-4. On the other hand, the G pixel 100 (2, 7)is provided with a pixel electrode 106-7 connected to the horizontalsignal line 104-3 whereas the B pixel 100 (2, 8) is provided with apixel electrode 106-8 connected to the horizontal signal line 104-4.

On top of that, every pixel 100 is connected to a reset line 107 and aread signal line 108.

In the image sensor having such a configuration, the R pixels 100 (1,1), 100 (1, 3), 100 (1, 5) and 100 (1, 7) laid out in the horizontaldirection are selected by the horizontal signal line 104-1, and a pixelsignal is read out from the vertical signal lines 103-1 to 103-4connected to the Bayer column of each of the R pixels 100.

By the same token, the G pixels 100 (1, 2), 100 (1, 4), 100 (1, 6) and100 (1, 8) laid out in the horizontal direction are selected by thehorizontal signal line 104-2, and a pixel signal is read out from thevertical signal lines 103-1 to 103-4 connected to the Bayer column ofeach of the G pixels.

In the same way, the G pixels 100 (2, 1), 100 (2, 3), 100 (2, 5) and 100(2, 7) laid out in the horizontal direction are selected by thehorizontal signal line 104-3, and a pixel signal is read out from thevertical signal lines 103-1 to 103-4 connected to the Bayer column ofeach of the G pixels.

Likewise, the B pixels 100 (2, 2), 100 (2, 4), 100 (2, 6) and 100 (2, 8)laid out in the horizontal direction are selected by the horizontalsignal line 104-4, and a pixel signal is read out from the verticalsignal lines 103-1 to 103-4 connected to the Bayer column of each of theB pixels.

Explanations with reference to diagrams of FIGS. 5A and 5B are added asfollows. FIG. 5A is a diagram provided for a read operation carried outin an all-pixel read mode whereas FIG. 5B is a diagram provided for aread operation carried out in a ½ thinned-out read mode. In the case ofthe read operation carried out in an all-pixel read mode, in order toread out a pixel signal from each of 4 pixels composing the Bayer array101-1, it is necessary to select each of the horizontal signal lines104-1 to 104-4 and, then, read out the pixel signals. Thus, 4 readoperations need to be carried out.

In addition, also in the case of the read operation carried out in a ½thinned-out read mode, in order to read out a pixel signal from each of4 pixels composing the Bayer array 101-1, it is necessary to select eachof the horizontal signal lines 104-1 to 104-4 and, then, read out thepixel signals. Thus, also in the case of the read operation carried outin a ½ thinned-out read mode, 4 read operations need to be carried out.

As described above, both in the case of the read operation carried outin an all-pixel read mode and in the case of the read operation carriedout in a ½ thinned-out read mode, in order to read out pixel signals of1 Bayer array (consisting of an R pixel, a G pixel, a G pixel and a Bpixel), 4 read operations are demanded.

By reducing the number of operations to read out a pixel signal byselecting a horizontal signal line, a high processing speed can beconceivably realized. In addition, sensitivity deteriorationsaccompanying the increased number of pixels can also be conceivablyimproved as well.

Addressing the problems described above, inventors of the presentembodiment have innovated an image processing apparatus capable ofrealizing a high processing speed and improving sensitivitydeteriorations accompanying the increased number of pixels employed inthe image processing apparatus.

In accordance with an embodiment of the present invention, there isprovided an image processing apparatus having a plurality of Bayerarrays each including 4 pixels sharing a common electrode which isconnected to a vertical signal line. Each of the pixels has a pixelelectrode which is connected to a horizontal signal line. The locationof each of the horizontal signal lines and the location of each of thepixel electrodes each connected to one of the horizontal signal linesare determined so that the locations in a neighboring Bayer array are amirror image of the counterpart locations in another Bayer arrayadjacent to the neighboring Bayer array.

In addition, it is also possible to provide a configuration in which, ifthe pixel electrode of a neighboring pixel included in a neighboringBayer array is placed on the upper side in the neighboring pixel, thepixel electrode of another pixel included in another Bayer arrayadjacent to the neighboring Bayer array in the horizontal direction isalso placed on the upper side in the other pixel. If the pixel electrodeof such a neighboring pixel is placed on the lower side in theneighboring pixel, on the other hand, the pixel electrode of suchanother pixel is also placed on the lower side in the other pixel.

In addition, it is also possible to provide a configuration in which thepixel electrode of the neighboring pixel and the pixel electrode of theother pixel are connected to each other by the same one of thehorizontal signal lines.

In addition, it is also possible to provide a configuration in which apixel signal is read out from any neighboring one of the pixels byproperly selecting a horizontal signal line.

In addition, it is also possible to provide a configuration in which:

a pixel located on the left lower side in the Bayer array to serve asone of the 4 pixels pertaining to the Bayer array is used as the firstpixel;

a pixel located on the right lower side in the Bayer array to serve asone of the 4 pixels pertaining to the Bayer array is used as the secondpixel;

a pixel located on the left upper side in the Bayer array to serve asone of the 4 pixels pertaining to the Bayer array is used as the thirdpixel;

a pixel located on the right upper side in the Bayer array to serve asone of the 4 pixels pertaining to the Bayer array is used as the fourthpixel;

each of the horizontal signal lines is stretched in a horizontaldirection referred to as the direction of every row;

each of the vertical signal lines is stretched in a vertical directionreferred to as the direction of every column;

the first pixel of a Bayer array denoted by a notation including an oddcolumn number and the second pixel of a Bayer array denoted by anotation including an even column number are connected to each other bya first horizontal signal line;

the second pixel of a Bayer array denoted by a notation including an oddcolumn number and the first pixel of a Bayer array denoted by a notationincluding an even column number are connected to each other by a secondhorizontal signal line;

the third pixel of a Bayer array denoted by a notation including an oddcolumn number and the fourth pixel of a Bayer array denoted by anotation including an even column number are connected to each other bya third horizontal signal line; and

the fourth pixel of a Bayer array denoted by a notation including an oddcolumn number and the third pixel of a Bayer array denoted by a notationincluding an even column number are connected to each other by a fourthhorizontal signal line.

In addition, it is also possible to provide a configuration in whichpixel signals are read out from the pixels by selecting the firsthorizontal signal line for a Bayer array denoted by a notation includingan odd column number and selecting the third horizontal signal line fora Bayer array denoted by a notation including an even column number.

In addition, it is also possible to provide a configuration in whichpixel signals are read out from the pixels by selecting the secondhorizontal signal line for a Bayer array denoted by a notation includingan odd column number and selecting the fourth horizontal signal line fora Bayer array denoted by a notation including an even column number.

In addition, it is also possible to provide a configuration in whichpixel signals are read out from the pixels by selecting the thirdhorizontal signal line for a Bayer array denoted by a notation includingan odd column number and selecting the first horizontal signal line fora Bayer array denoted by a notation including an even column number.

In addition, it is also possible to provide a configuration in whichpixel signals are read out from the pixels by selecting the thirdhorizontal signal line for a Bayer array denoted by a notation includingan odd column number and selecting the first horizontal signal line fora Bayer array denoted by a notation including an even column number and,then, pixel signals are read out from the pixels by selecting the secondhorizontal signal line for a Bayer array denoted by a notation includingan odd column number and selecting the fourth horizontal signal line fora Bayer array denoted by a notation including an even column number.

In addition, it is also possible to provide a configuration in which:

the 4 pixels composing the Bayer array is an R pixel, a G1 pixel, a G2pixel and a B pixel;

each of the horizontal signal lines is stretched in a horizontaldirection referred to as the direction of every row;

each of the vertical signal lines is stretched in a vertical directionreferred to as the direction of every column;

the R pixel of a Bayer array denoted by a notation including an oddcolumn number and the G1 pixel of a Bayer array denoted by a notationincluding an even column number are connected to each other by a firsthorizontal signal line;

the G1 pixel of a Bayer array denoted by a notation including an oddcolumn number and the R pixel of a Bayer array denoted by a notationincluding an even column number are connected to each other by a secondhorizontal signal line;

the G2 pixel of a Bayer array denoted by a notation including an oddcolumn number and the B pixel of a Bayer array denoted by a notationincluding an even column number are connected to each other by a thirdhorizontal signal line; and

the B pixel of a Bayer array denoted by a notation including an oddcolumn number and the G2 pixel of a Bayer array denoted by a notationincluding an even column number are connected to each other by a fourthhorizontal signal line.

In addition, it is also possible to provide a configuration in which, ifthe pixel electrode of a neighboring pixel included in a neighboringBayer array is placed on the upper side in the neighboring pixel, thepixel electrode of another pixel included in another Bayer arrayadjacent to the neighboring Bayer array in the vertical direction isplaced on the lower side in the other pixel. If the pixel electrode ofthe neighboring pixel is placed on the lower side in the neighboringpixel, on the other hand, the pixel electrode of the other pixel isplaced on the upper side in the other pixel.

In addition, it is also possible to provide a configuration in which:

a pixel located on the left lower side in the Bayer array to serve asone of the 4 pixels pertaining to the Bayer array is used as the firstpixel;

a pixel located on the right lower side in the Bayer array to serve asone of the 4 pixels pertaining to the Bayer array is used as the secondpixel;

a pixel located on the left upper side in the Bayer array to serve asone of the 4 pixels pertaining to the Bayer array is used as the thirdpixel;

a pixel located on the right upper side in the Bayer array to serve asone of the 4 pixels pertaining to the Bayer array is used as the fourthpixel;

each of the horizontal signal lines is stretched in a horizontaldirection referred to as the direction of every row;

each of the vertical signal lines is stretched in a vertical directionreferred to as the direction of every column;

the first pixel of a Bayer array denoted by a notation including an oddcolumn number and the first pixel of a Bayer array denoted by a notationincluding an even column number are connected to each other by a firsthorizontal signal line;

the second pixel of a Bayer array denoted by a notation including an oddcolumn number and the second pixel of a Bayer array denoted by anotation including an even column number are connected to each other bya second horizontal signal line;

the third pixel of a Bayer array denoted by a notation including an oddcolumn number and the third pixel of a Bayer array denoted by a notationincluding an even column number are connected to each other by a thirdhorizontal signal line;

the fourth pixel of a Bayer array denoted by a notation including an oddcolumn number and the fourth pixel of a Bayer array denoted by anotation including an even column number are connected to each other bya fourth horizontal signal line; and

a Bayer array denoted by a notation including an even row number isplaced at a location shifted away from a Bayer array denoted by anotation including an odd row number by a distance equal to ½ the sizeof each Bayer array.

In addition, it is also possible to provide a configuration in whichpixel signals are read out from the pixels by selecting the fourthhorizontal signal line for a Bayer array denoted by a notation includingan odd column number and selecting the second horizontal signal line fora Bayer array denoted by a notation including an even column number andpixel signals are read out from the pixels by selecting the thirdhorizontal signal line for a Bayer array denoted by a notation includingan odd column number and selecting the first horizontal signal line fora Bayer array denoted by a notation including an even column number.

In addition, it is also possible to provide a configuration in which:

the 4 pixels composing the Bayer array is an R pixel, a G1 pixel, a G2pixel and a B pixel;

each of the horizontal signal lines is stretched in a horizontaldirection referred to as the direction of every row;

each of the vertical signal lines is stretched in a vertical directionreferred to as the direction of every column;

the R pixel of a Bayer array denoted by a notation including an oddcolumn number and the R pixel of a Bayer array denoted by a notationincluding an even column number are connected to each other by a firsthorizontal signal line;

the G1 pixel of a Bayer array denoted by a notation including an oddcolumn number and the G1 pixel of a Bayer array denoted by a notationincluding an even column number are connected to each other by a secondhorizontal signal line;

the G2 pixel of a Bayer array denoted by a notation including an oddcolumn number and the G2 pixel of a Bayer array denoted by a notationincluding an even column number are connected to each other by a thirdhorizontal signal line;

the B pixel of a Bayer array denoted by a notation including an oddcolumn number and the B pixel of a Bayer array denoted by a notationincluding an even column number are connected to each other by a fourthhorizontal signal line; and a Bayer array denoted by a notationincluding an even row number is placed at a location shifted away from aBayer array denoted by a notation including an odd row number by adistance equal to ½ the size of each Bayer array.

In accordance with another embodiment of the present invention, there isprovided an image processing method for an image processing apparatushaving a plurality of Bayer arrays each including 4 pixels sharing acommon electrode which is connected to a vertical signal line. Each ofthe pixels has a pixel electrode which is connected to a horizontalsignal line. The location of each of the horizontal signal lines and thelocation of each of the pixel electrodes each connected to one of thehorizontal signal lines are determined so that the locations in aneighboring Bayer array are a mirror image of the counterpart locationsin another Bayer array adjacent to the neighboring Bayer array. Inaccordance with the image processing method, a pixel signal is read outfrom a neighboring one of the pixels by properly selecting a horizontalsignal line connected to the neighboring pixel from the horizontalsignal lines.

As described above, in the image processing apparatus according to anembodiment of the present invention and the image processing methodaccording to the other embodiment of the present invention:

a plurality of Bayer arrays each include 4 pixels sharing a commonelectrode which is connected to a vertical signal line;

each of the pixels has a pixel electrode which is connected to ahorizontal signal line;

the location of each of the horizontal signal lines and the location ofeach of the pixel electrodes each connected to one of the horizontalsignal lines are determined so that the locations in a neighboring Bayerarray are a mirror image of the counterpart locations in another Bayerarray adjacent to the neighboring Bayer array; and a pixel signal isread out from a neighboring one of the pixels by properly selecting ahorizontal signal line.

In accordance with a further embodiment of the present invention, thereis provided a manufacturing apparatus for manufacturing an imageprocessing apparatus in which:

a plurality of Bayer arrays each include 4 pixels sharing a commonelectrode connected to a vertical signal line;

each of the pixels has a pixel electrode connected to a horizontalsignal line; and

the location of each of the horizontal signal lines and the location ofeach of the pixel electrodes each connected to one of the horizontalsignal lines are determined so that the locations in a neighboring Bayerarray are a mirror image of the counterpart locations in another Bayerarray adjacent to the neighboring Bayer array.

By making use of the manufacturing apparatus according to the furtherembodiment of the present invention, it is possible to manufacture animage processing apparatus in which:

a plurality of Bayer arrays each include 4 pixels sharing a commonelectrode connected to a vertical signal line;

each of the pixels has a pixel electrode connected to a horizontalsignal line; and

the location of each of the horizontal signal lines and the location ofeach of the pixel electrodes each connected to one of the horizontalsignal lines are determined so that the locations in a neighboring Bayerarray are a mirror image of the counterpart locations in another Bayerarray adjacent to the neighboring Bayer array.

In accordance with the present embodiment, the number of operations toread out a pixel signal can be reduced. In addition, by reducing thenumber of operations to read out a pixel signal, the speed of theprocessing as a whole can be increased.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing the configuration of a typical example ofthe existing image sensor;

FIG. 2 is a diagram showing the configuration of a typical example ofthe existing image sensor;

FIG. 3 is an explanatory diagram to be referred to in description of thelocations of pixel electrodes in the existing image sensor;

FIG. 4 is a circuit diagram showing the existing image sensor;

FIGS. 5A and 5B are an explanatory diagrams to be referred to indescription of operations to read out pixel signals from the existingimage sensor;

FIG. 6 is a diagram showing the configuration of an image sensoraccording to an embodiment of the present invention;

FIG. 7 is an explanatory diagram to be referred to in description of thelocations of pixel electrodes in an image sensor;

FIG. 8 is a circuit diagram showing the image sensor shown in thediagram of FIG. 7;

FIG. 9 is an explanatory diagram to be referred to in description ofread operations carried out in an all-pixel read mode;

FIG. 10 is an explanatory diagram to be referred to in description ofread operations carried out in a thinned-out read mode;

FIG. 11 is an explanatory diagram to be referred to in description ofread operations carried out in a thinned-out read mode;

FIG. 12 is an explanatory diagram to be referred to in description ofread operations carried out in a thinned-out read mode;

FIG. 13 is an explanatory diagram to be referred to in description ofread operations carried out in a thinned-out read mode;

FIG. 14 is a diagram showing the configuration of an image sensoraccording to another embodiment of the present invention;

FIG. 15 is an explanatory diagram to be referred to in description ofthe layout of pixel electrodes in an image sensor;

FIG. 16 is a circuit diagram showing the image sensor shown in thediagram of FIG. 15;

FIG. 17 is an explanatory diagram to be referred to in description ofread operations carried out in an all-pixel read mode; and

FIG. 18 is an explanatory diagram to be referred to in description ofread operations carried out in a thinned-out read mode.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of the present invention are explained byreferring to diagrams as follows.

First Embodiment

FIG. 6 is a diagram showing the configuration of an image processingapparatus according to a first embodiment of the present invention.Since the image processing apparatus provided by the present embodimentcan be applied to the image sensor, in the following description, it isassumed that the present embodiment is applied to the image sensor whichis taken as a typical example of the application of the presentembodiment.

The image sensor shown in the diagram of FIG. 6 employs R (Red), G(Green) and B (Blue) pixels laid out and connected to each other to forma pixel matrix composed of first to sixth rows and first to eighthcolumns. What is shown in the diagram of FIG. 6 is a portion of theimage sensor. That is to say, in addition to the R (Red), G (Green) andB (Blue) pixels provided along the first to sixth rows and the first toeighth columns, the image sensor also employs R (Red), G (Green) and B(Blue) pixels provided along rows other than the first to sixth rows andalong columns other than the first to eighth columns.

In the following description, reference notation 200 (m, n) denotes apixel provided at the intersection of the mth row and the nth column.Every row is oriented in the horizontal direction, which is thedirection of the horizontal signal lines. On the other hand, everycolumn is oriented in the vertical direction, which is the direction ofthe vertical signal lines. For example, a pixel 200 (2, 1) is a pixellocated at the intersection of the second row and the first column.

A configuration constructed in the horizontal direction is explainedbelow. The horizontal direction, which is the direction of the rows, isa direction from the left to the right in the diagram of FIG. 6. An Rpixel 200 (1, 1), a G pixel 200 (1, 2), an R pixel 200 (1, 3), a G pixel200 (1, 4), an R pixel 200 (1, 5), a G pixel 200 (1, 6), an R pixel 200(1, 7) and a G pixel 200 (1, 8) are laid out along the first row. By thesame token, a G pixel 200 (2, 1), a B pixel 200 (2, 2), a G pixel 200(2, 3), a B pixel 200 (2, 4), a G pixel 200 (2, 5), a B pixel 200 (2,6), a G pixel 200 (2, 7) and a B pixel 200 (2, 8) are laid out along thesecond row. The pixels 200 on the first and second rows form a first rowBayer array.

A second row Bayer array is provided at a location above the first rowBayer array. In the same way as the first row Bayer array, the secondrow Bayer array includes an R pixel 200 (3, 1), a G pixel 200 (3, 2), anR pixel 200 (3, 3), a G pixel 200 (3, 4), an R pixel 200 (3, 5), a Gpixel 200 (3, 6), an R pixel 200 (3, 7) and a G pixel 200 (3, 8) whichare laid out along the first row of the second row Bayer array as wellas a G pixel 200 (4, 1), a B pixel 200 (4, 2), a G pixel 200 (4, 3), a Bpixel 200 (4, 4), a G pixel 200 (4, 5), a B pixel 200 (4, 6), a G pixel200 (4, 7) and a B pixel 200 (4, 8) which are laid out along the secondrow of the second row Bayer array.

A third row Bayer array is provided at a location above the second rowBayer array. In the same way as the second row Bayer array, the thirdrow Bayer array includes an R pixel 200 (5, 1), a G pixel 200 (5, 2), anR pixel 200 (5, 3), a G pixel 200 (5, 4), an R pixel 200 (5, 5), a Gpixel 200 (5, 6), an R pixel 200 (5, 7) and a G pixel 200 (5, 8) whichare laid out along the first row of the third row Bayer array as well asa G pixel 200 (6, 1), a B pixel 200 (6, 2), a G pixel 200 (6, 3), a Bpixel 200 (6, 4), a G pixel 200 (6, 5), a B pixel 200 (6, 6), a G pixel200 (6, 7) and a B pixel 200 (6, 8) which are laid out along the secondrow of the third row Bayer array.

Next, a configuration constructed in the vertical direction is explainedbelow. The vertical direction, which is the direction of the columns, isa direction from the top to the bottom in the diagram of FIG. 6. An Rpixel 200 (1, 1), a G pixel 200 (2, 1), an R pixel 200 (3, 1), a G pixel200 (4, 1), an R pixel 200 (5, 1) and a G pixel 200 (6, 1) are laid outalong the first column. By the same token, a G pixel 200 (1, 2), a Bpixel 200 (2, 2), a G pixel 200 (3, 2), a B pixel 200 (4, 2), a G pixel200 (5, 2) and a B pixel 200 (6, 2) are laid out along the secondcolumn. The pixels on the first and second columns form a first columnBayer array.

In the diagram of FIG. 6, a second column Bayer array is provided on theright-hand side of the first column Bayer array. In the same way as thefirst column Bayer array, the second column Bayer array includes an Rpixel 200 (1, 3), a G pixel 200 (2, 3), an R pixel 200 (3, 3), a G pixel200 (4, 3), an R pixel 200 (5, 3) and a G pixel 200 (6, 3) which arelaid out along the first column of the second column Bayer array as wellas a G pixel 200 (1, 4), a B pixel 200 (2, 4), a G pixel 200 (3, 4), a Bpixel 200 (4, 4), a G pixel 200 (5, 4) and a B pixel 200 (6, 4) whichare laid out along the second column of the second column Bayer array.

In the diagram of FIG. 6, a third column Bayer array is provided on theright-hand side of the second column Bayer array. In the same way as thesecond column Bayer array, the third column Bayer array includes an Rpixel 200 (1, 5), a G pixel 200 (2, 5), an R pixel 200 (3, 5), a G pixel200 (4, 5), an R pixel 200 (5, 5) and a G pixel 200 (6, 5) which arelaid out along the first column of the third column Bayer array as wellas a G pixel 200 (1, 6), a B pixel 200 (2, 6), a G pixel 200 (3, 6), a Bpixel 200 (4, 6), a G pixel 200 (5, 6) and a B pixel 200 (6, 6) whichare laid out along the second column of the third column Bayer array.

In the diagram of FIG. 6, a fourth column Bayer array is provided on theright-hand side of the third column Bayer array. In the same way as thethird column Bayer array, the fourth column Bayer array includes an Rpixel 200 (1, 7), a G pixel 200 (2, 7), an R pixel 200 (3, 7), a G pixel200 (4, 7), an R pixel 200 (5, 7) and a G pixel 200 (6, 7) which arelaid out along the first column of the fourth column Bayer array as wellas a G pixel 200 (1, 8), a B pixel 200 (2, 8), a G pixel 200 (3, 8), a Bpixel 200 (4, 8), a G pixel 200 (5, 8) and a B pixel 200 (6, 8) whichare laid out along the second column of the fourth column Bayer array.

In the image sensor shown in the diagram of FIG. 6, 4 pixels share acommon electrode 202 which is connected to a vertical signal line. Toput it more concretely, as an example, an R pixel 200 (1, 1), a G pixel200 (1, 2), a G pixel 200 (2, 1) and a B pixel 200 (2, 2) form a Bayerarray 201 (1, 1) which is provided with a common electrode 202 (1, 1).

By the same token, an R pixel 200 (1, 3), a G pixel 200 (1, 4), a Gpixel 200 (2, 3) and a B pixel 200 (2, 4) form a Bayer array 201 (1, 2)which is provided with a common electrode 202 (1, 2). In the same way,an R pixel 200 (1, 5), a G pixel 200 (1, 6), a G pixel 200 (2, 5) and aB pixel 200 (2, 6) form a Bayer array 201 (1, 3) which is provided witha common electrode 202 (1, 3). Likewise, an R pixel 200 (1, 7), a Gpixel 200 (1, 8), a G pixel 200 (2, 7) and a B pixel 200 (2, 8) form aBayer array 201 (1, 4) which is provided with a common electrode 202 (1,4).

Similarly, an R pixel 200 (3, 1), a G pixel 200 (3, 2), a G pixel 200(4, 1) and a B pixel 200 (4, 2) form a Bayer array 201 (2, 1) which isprovided with a common electrode 202 (2, 1). By the same token, an Rpixel 200 (3, 3), a G pixel 200 (3, 4), a G pixel 200 (4, 3) and a Bpixel 200 (4, 4) form a Bayer array 201 (2, 2) which is provided with acommon electrode 202 (2, 2). In the same way, an R pixel 200 (3, 5), a Gpixel 200 (3, 6), a G pixel 200 (4, 5) and a B pixel 200 (4, 6) form aBayer array 201 (2, 3) which is provided with a common electrode 202 (2,3). Likewise, an R pixel 200 (3, 7), a G pixel 200 (3, 8), a G pixel 200(4, 7) and a B pixel 200 (4, 8) form a Bayer array 201 (2, 4) which isprovided with a common electrode 202 (2, 4).

Similarly, an R pixel 200 (5, 1), a G pixel 200 (5, 2), a G pixel 200(6, 1) and a B pixel 200 (6, 2) form a Bayer array 201 (3, 1) which isprovided with a common electrode 202 (3, 1). By the same token, an Rpixel 200 (5, 3), a G pixel 200 (5, 4), a G pixel 200 (6, 3) and a Bpixel 200 (6, 4) form a Bayer array 201 (3, 2) which is provided with acommon electrode 202 (3, 2). In the same way, an R pixel 200 (5, 5), a Gpixel 200 (5, 6), a G pixel 200 (6, 5) and a B pixel 200 (6, 6) form aBayer array 201 (3, 3) which is provided with a common electrode 202 (3,3). Likewise, an R pixel 200 (5, 7), a G pixel 200 (5, 8), a G pixel 200(6, 7) and a B pixel 200 (6, 8) form a Bayer array 201 (3, 4) which isprovided with a common electrode 202 (3, 4).

The common electrode 202 (1, 1) of the Bayer array 201 (1, 1), thecommon electrode 202 (2, 1) of the Bayer array 201 (2, 1) and the commonelectrode 202 (3, 1) of the Bayer array 201 (3, 1) are connected to thevertical signal line 203-1. By the same token, the common electrode 202(1, 2) of the Bayer array 201 (1, 2), the common electrode 202 (2, 2) ofthe Bayer array 201 (2, 2) and the common electrode 202 (3, 2) of theBayer array 201 (3, 2) are connected to the vertical signal line 203-2.

In the same way, the common electrode 202 (1, 3) of the Bayer array 201(1, 3), the common electrode 202 (2, 3) of the Bayer array 201 (2, 3)and the common electrode 202 (3, 3) of the Bayer array 201 (3, 3) areconnected to the vertical signal line 203-3. By the same token, thecommon electrode 202 (1, 4) of the Bayer array 201 (1, 4), the commonelectrode 202 (2, 4) of the Bayer array 201 (2, 4) and the commonelectrode 202 (3, 4) of the Bayer array 201 (3, 4) are connected to thevertical signal line 203-4.

As described above, each pixel 200 is provided also with a pixelelectrode 205 which is connected to a horizontal signal line 204. To bemore specific, the R pixel 200 (1, 1), the G pixel 200 (1, 4), the Rpixel 200 (1, 5) and the G pixel 200 (1, 8) which are laid out along thefirst row of the first row Bayer array are connected to the horizontalsignal line 204 (1, 1). By the same token, the G pixel 200 (1, 2), the Rpixel 200 (1, 3), the G pixel 200 (1, 6) and the R pixel 200 (1, 7)which are laid out along the first row of the first row Bayer array areconnected to the horizontal signal line 204 (1, 2).

In the same way, the G pixel 200 (2, 1), the B pixel 200 (2, 4), the Gpixel 200 (2, 5) and the B pixel 200 (2, 8) which are laid out along thesecond row of the first row Bayer array are connected to the horizontalsignal line 204 (1, 3). Likewise, the B pixel 200 (2, 2), the G pixel200 (2, 3), the B pixel 200 (2, 6) and the G pixel 200 (2, 7) which arelaid out along the second row of the first row Bayer array are connectedto the horizontal signal line 204 (1, 4).

Similarly, the R pixel 200 (3, 1), the G pixel 200 (3, 4), the R pixel200 (3, 5) and the G pixel 200 (3, 8) which are laid out along the firstrow of the second row Bayer array are connected to the horizontal signalline 204 (2, 1). By the same token, the G pixel 200 (3, 2), the R pixel200 (3, 3), the G pixel 200 (3, 6) and the R pixel 200 (3, 7) which arelaid out along the first row of the second row Bayer array are connectedto the horizontal signal line 204 (2, 2).

In the same way, the G pixel 200 (4, 1), the B pixel 200 (4, 4), the Gpixel 200 (4, 5) and the B pixel 200 (4, 8) which are laid out along thesecond row of the second row Bayer array are connected to the horizontalsignal line 204 (2, 3). Likewise, the B pixel 200 (4, 2), the G pixel200 (4, 3), the B pixel 200 (4, 6) and the G pixel 200 (4, 7) which arelaid out along the second row of the second row Bayer array areconnected to the horizontal signal line 204 (2, 4).

Similarly, the R pixel 200 (5, 1), the G pixel 200 (5, 4), the R pixel200 (5, 5) and the G pixel 200 (5, 8) which are laid out along the firstrow of the third row Bayer array are connected to the horizontal signalline 204 (3, 1). By the same token, the G pixel 200 (5, 2), the R pixel200 (5, 3), the G pixel 200 (5, 6) and the R pixel 200 (5, 7) which arelaid out along the first row of the third row Bayer array are connectedto the horizontal signal line 204 (3, 2).

In the same way, the G pixel 200 (6, 1), the B pixel 200 (6, 4), the Gpixel 200 (6, 5) and the B pixel 200 (6, 8) which are laid out along thesecond row of the third row Bayer array are connected to the horizontalsignal line 204 (3, 3). Likewise, the B pixel 200 (6, 2), the G pixel200 (6, 3), the B pixel 200 (6, 6) and the G pixel 200 (6, 7) which arelaid out along the second row of the third row Bayer array are connectedto the horizontal signal line 204 (3, 4).

By referring to a diagram of FIG. 7, the following description furtherdescribes a relation between the pixel electrodes 205 each provided fora pixel 200 and the horizontal signal lines 204 each connected to one ofthe pixel electrodes 205. FIG. 7 is a diagram showing a portion of theimage sensor shown in the diagram of FIG. 6. FIG. 8 is a diagram showingthe circuit of the partial image sensor shown in the diagram of FIG. 7.The diagrams of FIGS. 7 and 8 are obtained by extracting the Bayerarrays 201 (1, 1), 201 (1, 2), 201 (1, 3) and 201 (1, 4) from the imagesensor shown in the diagram of FIG. 6.

For example, let attention be paid to the Bayer array 201 (1, 1)including the R pixel 200 (1, 1) and the G pixel 200 (1, 2) which areadjacent to each other in the row direction. The R pixel 200 (1, 1) hasa pixel electrode 205 (1, 1) on the lower side in the R pixel 200 (1, 1)whereas the G pixel 200 (1, 2) has a pixel electrode 205 (1, 2) on theupper side in the G pixel 200 (1, 2).

The Bayer array 201 (1, 1) also includes the G pixel 200 (2, 1) and theB pixel 200 (2, 2) which are adjacent to each other in the rowdirection. By the same token, the G pixel 200 (2, 1) has a pixelelectrode 205 (2, 1) on the lower side in the G pixel 200 (2, 1) whereasthe B pixel 200 (2, 2) has a pixel electrode 205 (2, 2) on the upperside in the B pixel 200 (2, 2).

That is to say, pixel electrodes 205 adjacent to each other in the rowdirection inside the Bayer array 201 (1, 1) are placed alternately onthe lower and upper sides of the pixels 200 of the Bayer array 201 (1,1). In addition, each of the pixel electrodes 205 adjacent to each otherin the row direction inside the Bayer array 201 (1, 1) is connected toone of different horizontal signal lines 204.

In addition, for example, let attention be paid to the Bayer array 201(1, 1) including the R pixel 200 (1, 1) and the G pixel 200 (2, 1) whichare adjacent to each other in the column direction. The R pixel 200 (1,1) has a pixel electrode 205 (1, 1) on the lower side in the R pixel 200(1, 1) whereas the G pixel 200 (2, 1) has a pixel electrode 205 (2, 1)also on the lower side in the G pixel 200 (2, 1).

The Bayer array 201 (1, 1) also includes the G pixel 200 (1, 2) and theB pixel 200 (2, 2) which are adjacent to each other in the columndirection. By the same token, the G pixel 200 (1, 2) has a pixelelectrode 205 (1, 2) on the upper side in the G pixel 200 (1, 2) whereasthe B pixel 200 (2, 2) has a pixel electrode 205 (2, 2) also on thelower side in the B pixel 200 (2, 2).

That is to say, pixel electrodes 205 adjacent to each other in thecolumn direction inside the Bayer array 201 (1, 1) are placed on thesame lower or upper side in the pixels 200 of the Bayer array 201 (1,1). In addition, each of the pixel electrodes 205 adjacent to each otherin the row direction inside the Bayer array 201 (1, 1) is connected toone of different horizontal signal lines 204.

The pixel electrodes 205 of adjacent pixels 200 in the Bayer array 201are placed at locations which are related to each other as describedabove. The following description explains relations between thelocations of the pixel electrodes 205 of pixels 200 in Bayer arrays 201adjacent to each other in the row direction. For example, let attentionbe paid to the Bayer arrays 201 (1, 1) and 201 (1, 2) which are adjacentto each other in the row direction. The pixel electrode 205 (1, 2) ofthe G pixel 200 (1, 2) in the Bayer array 201 (1, 1) is placed on theupper side in the G pixel 200 (1, 2) whereas the pixel electrode 205 (1,3) of the R pixel 200 (1, 3) included in the Bayer array 201 (1, 2) as apixel 200 adjacent to the G pixel 200 (1, 2) is placed also on the upperside in the R pixel 200 (1, 3). By the same token, the pixel electrode205 (2, 2) of the B pixel 200 (2, 2) in the Bayer array 201 (1, 1) isplaced on the upper side in the B pixel 200 (2, 2) whereas the pixelelectrode 205 (2, 3) of the G pixel 200 (2, 3) included in the Bayerarray 201 (1, 2) as a pixel 200 adjacent to the B pixel 200 (2, 2) isplaced also on the upper side in the G pixel 200 (2, 3).

A specific Bayer array 201 includes pixels 200 adjacent in the rowdirection to pixels 200 in another Bayer array 201 adjacent to thespecific Bayer array 201 in the row direction. As described above, thepixel electrodes 205 of the pixels 200 in the specific Bayer array 201and the pixel electrodes 205 of the pixels 200 in the adjacent Bayerarray 201 are placed on the upper side. In addition, the pixel electrode205 of a specific pixel 200 included in a specific Bayer array 201 isconnected by a horizontal signal line 204 to the pixel electrode 205 ofa pixel 200 included in the other Bayer array 201 as a pixel 200adjacent to the specific pixel 200 in the row direction.

Let attention be paid to another pair of adjacent Bayer arrays 201. Tobe more specific, for example, let attention be paid to the Bayer arrays201 (1, 2) and 201 (1, 3) which are adjacent to each other in the rowdirection. The pixel electrode 205 (1, 4) of the G pixel 200 (1, 4) inthe Bayer array 201 (1, 2) is placed on the lower side in the G pixel200 (1, 4) whereas the pixel electrode 205 (1, 5) of the R pixel 200 (1,5) included in the Bayer array 201 (1, 3) as a pixel 200 adjacent to theG pixel 200 (1, 4) is placed also on the lower side in the R pixel 200(1, 5). By the same token, the pixel electrode 205 (2, 4) of the B pixel200 (2, 4) in the Bayer array 201 (1, 2) is placed on the lower side inthe B pixel 200 (2, 4) whereas the pixel electrode 205 (2, 5) of the Gpixel 200 (2, 5) included in the Bayer array 201 (1, 3) as a pixel 200adjacent to the B pixel 200 (2, 4) is placed also on the lower side inthe G pixel 200 (2, 5).

A specific Bayer array 201 includes other pixels 200 adjacent in the rowdirection to other pixels 200 in another Bayer array 201 adjacent to thespecific Bayer array 201 in the row direction. In this case, however,the pixel electrodes 205 of the pixels 200 in the specific Bayer array201 and the pixel electrodes 205 of the pixels 200 in the adjacent Bayerarray 201 are placed on the lower side. In addition, the pixel electrode205 of a specific pixel 200 included in a specific Bayer array 201 isconnected by a horizontal signal line 204 to the pixel electrode 205 ofa pixel 200 included in the other Bayer array 201 as a pixel 200adjacent to the specific pixel 200 in the row direction.

That is to say, the pixel electrodes 205 of specific pixels 200 in anyspecific Bayer array 201 and the pixel electrodes 205 of pixels 200included in a Bayer array 201 adjacent to the specific Bayer array 201as pixels 200 adjacent to the specific pixels are placed on the sameside, that is, either the lower or upper side in the pixels 200. Inaddition, the pixel electrode 205 of a specific pixel 200 included inany specific Bayer array 201 is connected by a horizontal signal line204 to the pixel electrode 205 of a pixel 200 included in a Bayer array201 adjacent to the specific Bayer array 201 as a pixel 200 adjacent tothe specific pixel 200.

The following description explains relations between the locations ofthe pixel electrodes 205 of pixels 200 in Bayer arrays 201 adjacent toeach other in the column direction. For example, let attention be paidto the Bayer arrays 201 (1, 1) and 201 (2, 1) which are adjacent to eachother in the column direction as shown in the diagram of FIG. 6. Thepixel electrodes 205 of pixels 200 included in the Bayer arrays 201 (1,1) and 201 (2, 1) as pixels 200 aligned along the same column of thepixel matrix are located on the same side, that is, either the lower orupper side in the pixels 200.

That is to say, the pixel electrodes 205 of specific pixels 200 in anyspecific Bayer array 201 and the pixel electrodes 205 of pixels 200included in a Bayer array 201 adjacent to the specific Bayer array 201in the column direction as pixels 200 adjacent to the specific pixels200 in the column direction are placed on the same side, that is, eitherthe lower or upper side in the pixels 200. In addition, the pixelelectrode 205 of the specific pixel 200 included in the specific Bayerarray 201 is connected to a horizontal signal line 204 different from ahorizontal signal line 204 connected to the pixel electrode 205 of theadjacent pixel 200 included in the adjacent Bayer array 201. However,the pixel electrode 205 of the specific pixel 200 included in thespecific Bayer array 201 is connected by a vertical signal line 203 tothe pixel electrode 205 of the adjacent pixel 200 included in theadjacent Bayer array 201.

The above description explains where the pixel electrodes 205 arelocated and how the pixel electrodes 205 are connected to each other bythe horizontal signal lines 204 and the vertical signal lines 203. Thefollowing description explains relations between the positions of thepixel electrodes 205 of pixels 200 in any specific Bayer array 201 andthe positions of the pixel electrodes 205 of pixels 200 in a Bayer array201 adjacent to the specific Bayer array 201. For example, let attentionbe paid to the Bayer arrays 201 (1, 1) and 201 (1, 2) which are adjacentto each other. The positions of the pixel electrodes 205 of pixels 200in the Bayer array 201 (1, 1) are the mirror image of the positions ofthe pixel electrodes 205 of pixels 200 in the Bayer array 201 (1, 2)and, conversely, the positions of the pixel electrodes 205 of pixels 200in the Bayer array 201 (1, 2) are the mirror image of the positions ofthe pixel electrodes 205 of pixels 200 in the Bayer array 201 (1, 1).

The connections of the pixel electrodes 205 and the horizontal signallines 204 are explained below. That is to say, the pixel electrodes 205are wired to the horizontal signal lines 204 as follows.

As shown in the diagrams of FIGS. 7 and 8, 1 Bayer array includes 4pixels, i. e., an R pixel, a G1 pixel, a G2 pixel and a B pixel. The 4square pixels are arranged in the Bayer array to create a square shapeof the array. Let attention be paid to 2 such Bayer arrays adjacent toeach other. In this case, the R pixel of a first one of the 2 Bayerarrays is connected to the G1 pixel of the second Bayer array adjacentto the first Bayer array in the horizontal direction, that is, the rowdirection in this case, by a first horizontal signal line. In general,in a plurality of Bayer arrays, the R pixel of an odd-numbered Bayerarray is always connected to the G1 pixel of an even-numbered Bayerarray by a first horizontal signal line.

The connection of the R pixel of an even-numbered Bayer array to the G1pixel of an odd-numbered Bayer array by a first horizontal signal linein a plurality of Bayer arrays such as first and second Bayer arrays isexplained by associating the connection with the image sensor shown inthe diagram of FIG. 7 as follows. The first Bayer array corresponds tothe Bayer array 201 (1, 1) whereas the second Bayer array corresponds tothe Bayer array 201 (1, 2). The R pixel corresponds to the R pixel 200(1, 1) whereas the G1 pixel corresponds to the G pixel 200 (1, 4). Thefirst horizontal signal line corresponds to the horizontal signal line204 (1, 1).

A plurality of Bayer arrays arranged in the horizontal direction are theBayer arrays 201 (1, 1), 201 (1, 2), 201 (1, 3) and 201 (1, 4) shown inthe diagram of FIG. 7. The odd-numbered Bayer arrays are the Bayerarrays 201 (1, 1) and 201 (1, 3) which are each denoted by a notationincluding an odd column number used as a right-hand side subscript. TheR pixels 200 in the odd-numbered Bayer arrays 201 (1, 1) and 201 (1, 3)are the R pixels 200 (1, 1) and 200 (1, 5). By the same token, theeven-numbered Bayer arrays are the Bayer arrays 201 (1, 2) and 201 (1,4) which are each denoted by a notation including an even column numberused as a right-hand side subscript. The G1 pixels 200 in theeven-numbered G1 Bayer arrays 201 (1, 2) and 201 (1, 4) are the G1pixels 200 (1, 4) and 200 (1, 8). The 4 Bayer arrays 200 (1, 1), 200 (1,2), 200 (1,3) and 200 (1, 4) are connected to each other by the firsthorizontal signal line, which is the horizontal signal line 204 (1, 1).

For the sake of uniform notations, the horizontal signal line 204 (1, 2)is used as the second horizontal signal line, the horizontal signal line204 (1, 3) is used as the third horizontal signal line and thehorizontal signal line 204 (1, 4) is used as the fourth horizontalsignal line. In this way, in the following description, subscript n usedin reference notation 204 (m, n) denoting a horizontal signal line is aninteger indicating that the horizontal signal line 204 (m, n) is the nthhorizontal signal line. In the case of the horizontal signal line 204(1, 2) for example, subscript n has a value of 2 (that is, n=2). Thus,the horizontal signal line 204 (1, 2) is the second horizontal signalline.

In addition, subscript n used in reference notation 201 (m, n) denotinga Bayer array is an integer having a value indicating that the Bayerarray 201 (m, n) is an odd-numbered Bayer array or an even-numberedBayer array. In the case of the Bayer array 201 (1, 1) for example,subscript n has a value of 1 (that is, n=1). Thus, the Bayer array 201(1, 1) is an odd-numbered Bayer array. In the case of the Bayer array201 (1, 2), on the other hand, subscript n has a value of 2 (that is,n=2). Thus, the Bayer array 201 (1, 2) is an even-numbered Bayer array.

The notations described above are applied to the horizontal signal linesother than the first horizontal signal line as follows. The G1 pixel ofa first one of 2 adjacent Bayer arrays is connected to the R pixel ofthe second Bayer array adjacent to the first Bayer array in thehorizontal direction by a second horizontal signal line. In general, ina plurality of Bayer arrays, the G1 pixel of an odd-numbered Bayer arrayis always connected to the R pixel of an even-numbered Bayer array by asecond horizontal signal line.

By the same token, the G2 pixel of a first one of 2 adjacent Bayerarrays is connected to the B pixel of the second Bayer array adjacent tothe first Bayer array in the horizontal direction by a third horizontalsignal line. In general, in a plurality of Bayer arrays, the G2 pixel ofan odd-numbered Bayer array is always connected to the B pixel of aneven-numbered Bayer array by a third horizontal signal line.

In the same way, the B pixel of a first one of 2 adjacent Bayer arraysis connected to the G2 pixel of the second Bayer array adjacent to thefirst Bayer array in the horizontal direction by a fourth horizontalsignal line. In general, in a plurality of Bayer arrays, the B pixel ofan odd-numbered Bayer array is always connected to the G2 pixel of aneven-numbered Bayer array by a fourth horizontal signal line.

What has been described above is summarized as follows. A Bayer array iscomposed of 4 pixels. The pixel on the left lower side in the Bayerarray is referred to as the first pixel, the pixel on the right lowerside in the Bayer array is referred to as the second pixel, the pixel onthe left upper side in the Bayer array is referred to as the third pixeland the pixel on the right upper side in the Bayer array is referred toas the fourth pixel. The horizontal direction is taken as the directionof the horizontal signal lines whereas the vertical direction is takenas the direction of the vertical signal lines. In this case, the firstpixel in a Bayer array denoted by a notation including an odd columnnumber is connected to the second pixel in a Bayer array denoted by anotation including an even column number by a first horizontal signalline. The second pixel in a Bayer array denoted by a notation includingan odd column number is connected to the first pixel in a Bayer arraydenoted by a notation including an even column number by a secondhorizontal signal line. The third pixel in a Bayer array denoted by anotation including an odd column number is connected to the fourth pixelin a Bayer array denoted by a notation including an even column numberby a third horizontal signal line. The fourth pixel in a Bayer arraydenoted by a notation including an odd column number is connected to thethird pixel in a Bayer array denoted by a notation including an evencolumn number by a fourth horizontal signal line.

The method for connecting a pixel in a specific Bayer array to a pixelin another Bayer array adjacent to the specific Bayer array is no morethan a typical connection method. For example, the pixel in the specificBayer array can be combined with another pixel in the other Bayer arrayadjacent to the specific Bayer array to form a pair in conjunction withthe other pixel in the other Bayer array. Thus, there are 4 formed pixelpairs different from the 4 pixel pairs described above. The 2 pixels inevery pair are then connected to each other by one of the 4 horizontalsignal lines.

The following description explains read operations carried out by theimage sensor provided with a configuration in which each pixel isprovided with a pixel electrode which is connected to other pixelelectrodes as described above.

FIG. 9 is an explanatory diagram referred to in description of thenumber of read operations carried out in an all-pixel read mode. Inorder to read out pixel signals from the 4 pixels 200, that is, the R,G1, G2 and B pixels 200, of 1 Bayer array 201, it is necessary to carryout 4 read operations. To put it more concretely, for example, in orderto read out the pixel signal of the R pixel 200 (1, 1) of the Bayerarray 201 (1, 1), the pixel signal is read out through the horizontalsignal line 204 (1, 1), in order to read out the pixel signal of the Gpixel 200 (1, 2) of the Bayer array 201 (1, 1), the pixel signal is readout through the horizontal signal line 204 (1, 2), in order to read outthe pixel signal of the G pixel 200 (2, 1) of the Bayer array 201 (1,1), the pixel signal is read out through the horizontal signal line 204(1, 3) and, in order to read out the pixel signal of the B pixel 200 (2,2) of the Bayer array 201 (1, 1), the pixel signal is read out throughthe horizontal signal line 204 (1, 4).

Since a read operation is carried out to read out a pixel signal througheach of the first horizontal signal line 204 (1, 1), the secondhorizontal signal line 204 (1, 2), the third horizontal signal line 204(1, 3) and the fourth horizontal signal line 204 (1, 4), a total of 4read operations are demanded.

FIG. 10 is an explanatory diagram referred to in description of thenumber of read operations carried out in the ½ thinned-out read mode. Inorder to read out pixel signals from the 4 pixels 200, that is, the R,G1, G2 and B pixels 200, of 1 Bayer array, it is necessary to carry out2 read operations. In addition, in the ½ thinned-out read mode, pixelsignals are read out from pixels 200 by changing the selected horizontalsignal line 204.

In the typical example shown in the diagram of FIG. 10, pixel signalsare read out from one Bayer array through the first and third horizontalsignal lines.

Pixel signals are read out from Bayer arrays by changing the selectedhorizontal signal line from array to array. That is to say, in anoperation to read out a pixel signal from the first row Bayer array, thefirst horizontal signal line is selected, in an operation to read out apixel signal from the second row Bayer array, the third horizontalsignal line is selected, in an operation to read out a pixel signal fromthe third row Bayer array, the first horizontal signal line is selectedand, in an operation to read out a pixel signal from the fourth rowBayer array, the third horizontal signal line is selected.

That is to say, in this case, in general, for a Bayer array denoted by anotation including an odd row number, that is, for the first and thirdrow Bayer arrays for example, the first horizontal signal line isselected and, for a Bayer array denoted by a notation including an evenrow number, that is, for the second and fourth row Bayer arrays forexample, on the other hand, the third horizontal signal line isselected.

As an example, let attention be paid to the second and third row Bayerarrays. In the diagram of FIG. 10, the second row Bayer arrays includeBayer arrays 201 (2, 2) and 201 (2, 3) whereas the third row Bayerarrays include Bayer arrays 201 (3, 2) and 201 (3, 3). The followingdescription additionally explains a way to read out pixel signals fromthe second and third row Bayer arrays as shown in the diagram of FIG.10. By making use of the horizontal signal line 204 (3, 1) as the firsthorizontal signal line, pixel signals can be read out from the G pixel200 (5, 4) and the R pixel 200 (5, 5) of the Bayer arrays 201 (3, 2) and201 (3, 3) respectively. In addition, by making use of the horizontalsignal line 204 (2, 3) as the third horizontal signal line, pixelsignals can be read out from the B pixel 200 (4, 4) and the G pixel 200(4, 5) of the Bayer arrays 201 (2, 2) and 201 (2, 3) respectively.

The G pixel 200 (5, 4), the R pixel 200 (5, 5), the B pixel 200 (4, 4)and the G pixel 200 (4, 5) of the Bayer arrays 201 (3, 2), 201 (3, 3),201 (2, 2) and 201 (2, 3) respectively form 1 new Bayer array. Eventhough the G pixel 200 (5, 4), the R pixel 200 (5, 5), the B pixel 200(4, 4) and the G pixel 200 (4, 5) pertain to different Bayer arrays 201,these pixels 200 can be used respectively as 4 pixels, i. e., G2, R, Band G1 pixels of the new Bayer array so that the new Bayer array can becreated. Thus, processing can be carried out by forming the new Bayerarray from the 4 pixels 200, that is, the G pixel 200 (5, 4), the Rpixel 200 (5, 5), the B pixel 200 (4, 4) and the G pixel 200 (4, 5).

By doing so, in 2 horizontal scan operations, pixel signals of 1 Bayerarray can be read out. This read operation can be carried out byperforming the horizontal scan operation half the number of timesdemanded in the past as explained before by referring to the diagram ofFIG. 5B. Thus, the processing speed can be increased.

In the typical example shown in the diagram of FIG. 10, the first andthird horizontal signal lines are used. In another typical example shownin a diagram of FIG. 11, on the other hand, the second and fourthhorizontal signal lines are used. FIG. 11 is an explanatory diagramreferred to in description of the number of read operations carried outin the ½ thinned-out read mode for a case in which the second and fourthhorizontal signal lines are used.

Pixel signals are read out from Bayer arrays by changing the horizontalsignal line from array to array. That is to say, in an operation to readout a pixel signal from the first row Bayer array, the second horizontalsignal line is selected, in an operation to read out a pixel signal fromthe second row Bayer array, the fourth horizontal signal line isselected, in an operation to read out a pixel signal from the third rowBayer array, the second horizontal signal line is selected and, in anoperation to read out a pixel signal from the fourth row Bayer array,the fourth horizontal signal line is selected. In this case, for a Bayerarray denoted by a notation including an odd row number, the secondhorizontal signal line is selected and, for a Bayer array denoted by anotation including an even row number, on the other hand, the fourthhorizontal signal line is selected.

As an example, let attention be paid to the second and third row Bayerarrays. The following description additionally explains a way to readout pixel signals from the second and third row Bayer arrays. By makinguse of the horizontal signal line 204 (3, 2) as the second horizontalsignal line, pixel signals can be read out from the G pixel 200 (5, 2)and the R pixel 200 (5, 3). In addition, by making use of the horizontalsignal line 204 (2, 4) as the fourth horizontal signal line, pixelsignals can be read out from the B pixel 200 (4, 2) and the G pixel 200(4, 3).

The G pixel 200 (5, 2), the R pixel 200 (5, 3), the B pixel 200 (4, 2)and the G pixel 200 (4, 3) form a new Bayer array. Also in this case,even though the G pixel 200 (5, 2), the R pixel 200 (5, 3), the B pixel200 (4, 2) and the G pixel 200 (4, 3) pertain to different Bayer arrays,these pixels can be used respectively as 4 pixels, i. e., G2, R, B andG1 pixels of the new Bayer array so that the new Bayer array can becreated. Thus, processing can be carried out by forming the new Bayerarray from the 4 pixels 200, that is, the G pixel 200 (5, 2), the Rpixel 200 (5, 3), the B pixel 200 (4, 2) and the G pixel 200 (4, 3).

Also in the case of the typical example shown in the diagram of FIG. 11,in 2 horizontal scan operations, pixel signals of 1 Bayer array can beread out. This read operation can be carried out by performing thehorizontal scan operation half the number of times demanded in the past.Thus, the processing speed can be increased.

In another typical example shown in a diagram of FIG. 12, the first andthird horizontal signal lines are used. FIG. 12 is an explanatorydiagram referred to in description of the number of read operationscarried out in the ½ thinned-out read mode for a case in which the firstand third horizontal signal lines are used.

Pixel signals are read out from Bayer arrays by changing the horizontalsignal line from array to array. That is to say, in an operation to readout a pixel signal from the first row Bayer array, the third horizontalsignal line is selected, in an operation to read out a pixel signal fromthe second row Bayer array, the first horizontal signal line isselected, in an operation to read out a pixel signal from the third rowBayer array, the third horizontal signal line is selected and, in anoperation to read out a pixel signal from the fourth row Bayer array,the first horizontal signal line is selected. In this case, in general,for a Bayer array denoted by a notation including an odd row number, thethird horizontal signal line is selected and, for a Bayer array denotedby a notation including an even row number, on the other hand, the firsthorizontal signal line is selected.

Much like the typical example shown in the diagram of FIG. 10, in thetypical example shown in the diagram of FIG. 12, the first and thirdhorizontal signal lines are used. However, the order of selecting thefirst and third horizontal signal lines in the typical example shown inthe diagram of FIG. 12 is opposite to the order of selecting the firstand third horizontal signal lines in the typical example shown in thediagram of FIG. 10.

As an example, let attention be paid to the first and second row Bayerarrays. The following description additionally explains a way to readout pixel signals from the first and second row Bayer arrays. By makinguse of the horizontal signal line 204 (2, 1) as the first horizontalsignal line, pixel signals can be read out from the G pixel 200 (3, 4)and the R pixel 200 (3, 5). In addition, by making use of the horizontalsignal line 204 (1, 3) as the third horizontal signal line, pixelsignals can be read out from the B pixel 200 (2, 4) and the G pixel 200(2, 5).

The G pixel 200 (3, 4), the R pixel 200 (3, 5), the B pixel 200 (2, 4)and the G pixel 200 (2, 5) form a new Bayer array. Also in this case,even though the G pixel 200 (3, 4), the R pixel 200 (3, 5), the B pixel200 (2, 4) and the G pixel 200 (2, 5) pertain to different Bayer arrays,these pixels can be used respectively as 4 pixels, i. e., G2, R, B andG1 pixels of the new Bayer array so that the new Bayer array can becreated. Thus, processing can be carried out by forming a new Bayerarray from the 4 pixels 200, that is, the G pixel 200 (3, 4), the Rpixel 200 (3, 5), the B pixel 200 (2, 4) and the G pixel 200 (2, 5).

FIG. 13 is an explanatory diagram referred to in description of thenumber of read operations carried out in the ½ thinned-out read mode fora case in which the first to fourth horizontal signal lines are used.Pixel signals are read out from Bayer arrays by changing the horizontalsignal line from array to array. That is to say, in an operation to readout a pixel signal from the first row Bayer array, the second and thirdhorizontal signal lines are selected, in an operation to read out apixel signal from the second row Bayer array, the first and fourthhorizontal signal lines are selected, in an operation to read out apixel signal from the third row Bayer array, the second and thirdhorizontal signal lines are selected and, in an operation to read out apixel signal from the fourth row Bayer array, the first and fourthhorizontal signal lines are selected. In this case, in general, for aBayer array denoted by a notation including an odd row number, thesecond and third horizontal signal lines are selected and, for a Bayerarray denoted by a notation including an even row number, on the otherhand, the first and fourth horizontal signal lines are selected.

As an example, let attention be paid to the first and second row Bayerarrays. The following description additionally explains a way to readout pixel signals from the first and second row Bayer arrays. By makinguse of the horizontal signal line 204 (2, 1) as the first horizontalsignal line, pixel signals can be read out from the G pixel 200 (3, 4)and the R pixel 200 (3, 5). In addition, by making use of the horizontalsignal line 204 (1, 3) as the third horizontal signal line, pixelsignals can be read out from the B pixel 200 (2, 4) and the G pixel 200(2, 5). By carrying out the read operations in this way, pixel signalsof 1 Bayer array can be read out.

As described above, for a one-time read operation, the read operation iscarried out by selecting the third horizontal signal line in the case ofa Bayer array denoted by a notation including an odd row number andselecting the first horizontal signal line in the case of a Bayer arraydenoted by a notation including an even row number. In this way, adifferent horizontal signal line 204 can also be selected for each Bayerarray.

In addition, by carrying out a read operation with the horizontal signalline 204 (3, 2) selected as the second horizontal signal line, pixelsignals can be read out from the G pixel 200 (5, 2) and the R pixel 200(5, 3). Moreover, by carrying out a read operation with the horizontalsignal line 204 (2, 4) selected as the fourth horizontal signal line,pixel signals can be read out from the B pixel 200 (4, 2) and the Gpixel 200 (4, 3).

As described above, in general, for a one-time read operation, the readoperation is carried out by selecting the second horizontal signal linein the case of a Bayer array denoted by a notation including an odd rownumber and selecting the fourth horizontal signal line in the case of aBayer array denoted by a notation including an even row number.

As described above, a horizontal signal line selected for the first readoperation is different from a horizontal signal line selected for thesecond read operation whereas a horizontal signal line selected for aBayer array denoted by a notation including an odd row number isdifferent from a horizontal signal line selected for a Bayer arraydenoted by a notation including an even row number. Thus, in 2 readoperations, pixel signals for 2 Bayer arrays can be read out. Inaddition, by carrying out read operations in this way, it is possible tomake a Bayer array thinned out into a honeycomb shape.

The pixel electrodes of pixels including Bayer arrays are laid out andconnected to horizontal signal lines as described above so that thenumber of read operations (that is, the number of scan operations) canbe reduced. Thus, the time it takes to carry out all read operations canbe shortened. As a result, the processing speed can be increased.

Second Embodiment

FIG. 14 is a diagram showing a typical configuration of an image sensoraccording to a second embodiment of the present invention. In the imagesensor shown in the diagram of FIG. 14, shared pixels (a Bayer array)are laid out to form a honeycomb shape. Much like the first embodiment,1 Bayer array is configured to have 4 pixels, i. e., R, G1, G2 and Bpixels.

FIG. 14 shows a state of connections of R, G and B pixels atintersections of the first to sixth rows and the first to eighthcolumns. FIG. 14 shows a portion of the image sensor. However, the stateof connections of R, G and B pixels at intersections of rows other thanthe first to sixth rows and columns other than the first to eighthcolumns is the same as the state of connections of R, G and B pixels atintersections of the first to sixth rows and the first to eighthcolumns.

The horizontal-direction configuration of the image sensor is explainedas follows. It is to be noted that the horizontal direction is thedirection from the left to the right in the diagram of FIG. 14. On thefirst row of the image sensor, an R pixel 400 (1, 1), a G pixel 400 (1,2), an R pixel 400 (1, 3), a G pixel 400 (1, 4), an R pixel 400 (1, 5),a G pixel 400 (1, 6), an R pixel 400 (1, 7) and a G pixel 400 (1, 8) arelaid out. By the same token, on the second row of the image sensor, a Gpixel 400 (2, 1), a B pixel 400 (2, 2), a G pixel 400 (2, 3), a B pixel400 (2, 4), a G pixel 400 (2, 5), a B pixel 400 (2, 6), a G pixel 400(2, 7) and a B pixel 400 (2, 8) are laid out.

In addition, a Bayer array 401 (1, 1) is configured to have 4 pixels400, i. e., an R pixel 400 (1, 1), a G pixel 400 (1, 2), a G pixel 400(2, 1) and a B pixel 400 (2, 2). By the same token, a Bayer array 401(1, 2) is configured to have 4 pixels 400, i. e., an R pixel 400 (1, 3),a G pixel 400 (1, 4), a G pixel 400 (2, 3) and a B pixel 400 (2, 4).Similarly, a Bayer array 401 (1, 3) is configured to have 4 pixels 400,i. e., an R pixel 400 (1, 5), a G pixel 400 (1, 6), a G pixel 400 (2, 5)and a B pixel 400 (2, 6). Likewise, a Bayer array 401 (1, 4) isconfigured to have 4 pixels 400, i. e., an R pixel 400 (1, 7), a G pixel400 (1, 8), a G pixel 400 (2, 7) and a B pixel 400 (2, 8). The Bayerarrays 401 (1, 1), 401 (1, 2), 401 (1, 3) and 401 (1, 4) form theso-called first row Bayer array.

The second row Bayer array is placed above the first row Bayer arraydescribed above. Much like the first row Bayer array, on the first rowof the second row Bayer array, a G pixel 400 (3, 1), an R pixel 400 (3,2), a G pixel 400 (3, 3), an R pixel 400 (3, 4), a G pixel 400 (3, 5),an R pixel 400 (3, 6), a G pixel 400 (3, 7) and an R pixel 400 (3, 8)are laid out. By the same token, on the second row of the second rowBayer array, a B pixel 400 (4, 1), a G pixel 400 (4, 2), a B pixel 400(4, 3), a G pixel 400 (4, 4), a B pixel 400 (4, 5), a G pixel 400 (4,6), a B pixel 400 (4, 7) and a G pixel 400 (4, 8) are laid out.

In addition, a Bayer array 401 (2, 1) is configured to have 4 pixels400, i. e., a G pixel 400 (3, 1), an R pixel 400 (3, 2), a B pixel 400(4, 1) and a G pixel 400 (4, 2). By the same token, a Bayer array 401(2, 2) is configured to have 4 pixels 400, i. e., a G pixel 400 (3, 3),an R pixel 400 (3, 4), a B pixel 400 (4, 3) and a G pixel 400 (4, 4).Similarly, a Bayer array 401 (2, 3) is configured to have 4 pixels 400,i. e., a G pixel 400 (3, 5), an R pixel 400 (3, 6), a B pixel 400 (4, 5)and a G pixel 400 (4, 6). Likewise, a Bayer array 401 (2, 4) isconfigured to have 4 pixels 400, i. e., a G pixel 400 (3, 7), an R pixel400 (3, 8), a B pixel 400 (4, 7) and a G pixel 400 (4, 8). The Bayerarrays 401 (2, 1), 401 (2, 2), 401 (2, 3) and 401 (2, 4) form the secondrow Bayer array.

The second row Bayer array is placed at a location shifted away from thefirst row Bayer array by a distance of ½ the size of a Bayer array orthe size of one pixel. That is to say, as shown in the diagram of FIG.14, the Bayer array 401 (2, 1) of the second row Bayer array is placedat a location shifted away from the Bayer array 401 (1, 1) of the firstrow Bayer array by a distance of ½ the size of a Bayer array or the sizeof one pixel in the horizontal direction or the direction from the leftto the right in the diagram of FIG. 14. With regard to pixel locations,the G pixel 400 (3, 1) of the Bayer array 401 (2, 1) of the second rowBayer array is placed at a position above the B pixel 400 (2, 2) of theBayer array 401 (1, 1) of the first row Bayer array.

As described above, the first row of an even-numbered row Bayer arrayand the second row of an odd-numbered row Bayer array are separated fromeach other by a distance of ½ the size of a Bayer array or the size ofone pixel. In addition, the array of pixels in a Bayer array composingan even-numbered row Bayer array is made different from the array ofpixels in a Bayer array composing an odd-numbered row Bayer array. Thatis to say, the pixels in a Bayer array composing an odd-numbered rowBayer array are an R pixel on the lower left side, a G1 pixel on thelower right side, a G2 pixel on the upper left side and a B pixel on theupper right side. On the other hand, the pixels in a Bayer arraycomposing an even-numbered row Bayer array are a G1 pixel on the lowerleft side, a R pixel on the lower right side, a B pixel on the upperleft side and a G2 pixel on the upper right side.

The explanation with reference to the diagram of FIG. 14 is continued asfollows. The third row Bayer array is placed above the second row Bayerarray described above. Much like the second row Bayer arrays, on thefirst row of the third row Bayer array, an R pixel 400 (5, 1), a G pixel400 (5, 2), an R pixel 400 (5, 3), a G pixel 400 (5, 4), an R pixel 400(5, 5), a G pixel 400 (5, 6), an R pixel 400 (5, 7) and a G pixel 400(5, 8) are laid out. By the same token, on the second row of the thirdrow Bayer array, a G pixel 400 (6, 1), a B pixel 400 (6, 2), a G pixel400 (6, 3), a B pixel 400 (6, 4), a G pixel 400 (6, 5), a B pixel 400(6, 6), a G pixel 400 (6, 7) and a B pixel 400 (6, 8) are laid out.

In addition, a Bayer array 401 (3, 1) is configured to have 4 pixels400, i. e., an R pixel 400 (5, 1), a G pixel 400 (5, 2), a G pixel 400(6, 1) and a B pixel 400 (6, 2). By the same token, a Bayer array 401(3, 2) is configured to have 4 pixels 400, i. e., an R pixel 400 (5, 3),a G pixel 400 (5, 4), a G pixel 400 (6, 3) and a B pixel 400 (6, 4).Similarly, a Bayer array 401 (3, 3) is configured to have 4 pixels 400,i. e., an R pixel 400 (5, 5), a G pixel 400 (5, 6), a G pixel 400 (6, 5)and a B pixel 400 (6, 6). Likewise, a Bayer array 401 (3, 4) isconfigured to have 4 pixels 400, i. e., an R pixel 400 (5, 7), a G pixel400 (5, 8), a G pixel 400 (6, 7) and a B pixel 400 (6, 8).

The third row Bayer array is placed at a location separated away fromthe location of the second row Bayer array by a distance equal to ½ thesize of a Bayer array (that is, the size of one pixel) as the second rowBayer array is placed at a location separated away from the location ofthe first row Bayer array by a distance equal to ½ the size of a Bayerarray.

Next, a configuration constructed in the vertical direction is explainedbelow. The vertical direction, which is the direction of the columns, isa direction from the top to the bottom in the diagram of FIG. 14. An Rpixel 400 (1, 1), a G pixel 400 (2, 1), an R pixel 400 (5, 1) and a Gpixel 400 (6, 1) are laid out along the first column. On this column,pixels composing the second Bayer array are not included. By the sametoken, a G pixel 400 (1, 2), a B pixel 400 (2, 2), a G pixel 400 (3, 1),a B pixel 400 (4, 1), a G pixel 400 (5, 2) and a B pixel 400 (6, 2) arelaid out along the second column. This column includes pixels of thesecond column composing the first and third Bayer arrays and pixels ofthe first column composing the second Bayer array. The pixels on thefirst and second columns form a first column Bayer array.

In the diagram of FIG. 14, a second column Bayer array is provided onthe right-hand side of the first column Bayer array. In the same way asthe first column Bayer array, the second column Bayer array includes anR pixel 400 (1, 3), a G pixel 400 (2, 3), an R pixel 400 (3, 2), a Gpixel 400 (4, 2), an R pixel 400 (5, 3) and a G pixel 400 (6, 3) whichare laid out along the first column of the second column Bayer array aswell as a G pixel 400 (1, 4), a B pixel 400 (2, 4), a G pixel 400 (3,3), a B pixel 400 (4, 3), a G pixel 400 (5, 4) and a B pixel 400 (6, 4)which are laid out along the second column of the second column Bayerarray.

In the diagram of FIG. 14, a third column Bayer array is provided on theright-hand side of the second column Bayer array. In the same way as thesecond column Bayer array, the third column Bayer array includes an Rpixel 400 (1, 5), a G pixel 400 (2, 5), an R pixel 400 (3, 4), a G pixel400 (4, 4), an R pixel 400 (5, 5) and a G pixel 400 (6, 5) which arelaid out along the first column of the third column Bayer array as wellas a G pixel 400 (1, 6), a B pixel 400 (2, 6), a G pixel 400 (3, 5), a Bpixel 400 (4, 5), a G pixel 400 (5, 6) and a B pixel 400 (6, 6) whichare laid out along the second column of the third column Bayer array.

In the diagram of FIG. 14, a fourth column Bayer array is provided onthe right-hand side of the third column Bayer array. In the same way asthe third column Bayer array, the fourth column Bayer array includes anR pixel 400 (1, 7), a G pixel 400 (2, 7), an R pixel 400 (3, 6), a Gpixel 400 (4, 6), an R pixel 400 (5, 7) and a G pixel 400 (6, 7) whichare laid out along the first column of the fourth column Bayer array aswell as a G pixel 400 (1, 8), a B pixel 400 (2, 8), a G pixel 400 (3,7), a B pixel 400 (4, 7), a G pixel 400 (5, 8) and a B pixel 400 (6, 8)which are laid out along the second column of the fourth column Bayerarray.

In the image sensor shown in the diagram of FIG. 14, 4 pixels 400pertaining to a Bayer array 401 share a common electrode 402 which isconnected to a vertical signal line 403. To put it more concretely, aBayer array 401 (1, 1) is provided with a common electrode 402 (1, 1)whereas a Bayer array 401 (1, 2) is provided with a common electrode 402(1, 2). By the same token, a Bayer array 401 (1, 3) is provided with acommon electrode 402 (1, 3) whereas a Bayer array 401 (1, 4) is providedwith a common electrode 402 (1, 4).

In the same way, a Bayer array 401 (2, 1) is provided with a commonelectrode 402 (2, 1) whereas a Bayer array 401 (2, 2) is provided with acommon electrode 402 (2, 2). Likewise, a Bayer array 401 (2, 3) isprovided with a common electrode 402 (2, 3) whereas a Bayer array 401(2, 4) is provided with a common electrode 402 (2, 4).

Similarly, a Bayer array 401 (3, 1) is provided with a common electrode402 (3, 1) whereas a Bayer array 401 (3, 2) is provided with a commonelectrode 402 (3, 2). By the same token, a Bayer array 401 (3, 3) isprovided with a common electrode 402 (3, 3) whereas a Bayer array 401(3, 4) is provided with a common electrode 402 (3, 4).

The common electrode 402 (1, 1) of the Bayer array 401 (1, 1) and thecommon electrode 402 (3, 1) of the Bayer array 401 (3, 1) are connectedto each other by a vertical signal line 403-1. The common electrode 402(2, 1) of the Bayer array 401 (2, 1) is connected to a vertical signalline 403-2. The common electrode 402 (1, 2) of the Bayer array 401 (1,2) and the common electrode 402 (3, 2) of the Bayer array 401 (3, 2) areconnected to each other by a vertical signal line 403-3. The commonelectrode 402 (2, 2) of the Bayer array 401 (2, 2) is connected to avertical signal line 403-4.

The common electrode 402 (1, 3) of the Bayer array 401 (1, 3) and thecommon electrode 402 (3, 3) of the Bayer array 401 (3, 3) are connectedto each other by a vertical signal line 403-5. The common electrode 402(2, 3) of the Bayer array 401 (2, 3) is connected to a vertical signalline 403-6. The common electrode 402 (1, 4) of the Bayer array 401 (1,4) and the common electrode 402 (3, 4) of the Bayer array 401 (3, 4) areconnected to each other by a vertical signal line 403-7. The commonelectrode 402 (2, 4) of the Bayer array 401 (2, 4) is connected to avertical signal line 403-8.

As described above, a Bayer array 401 denoted by a notation including anodd column number is connected to a vertical signal line 403 differentfrom a vertical signal line 403 connected to a Bayer array 401 denotedby a notation including an even column number.

Every pixel 400 is provided with a pixel electrode 405 which isconnected to a horizontal signal line 404. The locations of the pixelelectrodes 405 of pixels 400 are explained by referring to diagrams ofFIGS. 15 and 16. The diagram of FIG. 15 is obtained by extracting thefirst and second row Bayer arrays from the image sensor shown in thediagram of FIG. 14. FIG. 16 is a diagram showing the circuit of theimage-sensor portion shown in the diagram of FIG. 15.

The pixel electrodes 405 (1, 1), 405 (1, 3), 405 (1, 5) and 405 (1, 7)of the R pixels 400 (1, 1), 400 (1, 3), 400 (1, 5) and 400 (1, 7)respectively which are laid out on the first row of the first row Bayerarray are connected to each other by the horizontal signal line 404 (1,1). By the same token, the pixel electrodes 405 (1, 2), 405 (1, 4), 405(1, 6) and 405 (1, 8) of the G pixels 400 (1, 2), 400 (1, 4), 400 (1, 6)and 400 (1, 8) respectively which are laid out on the first row of thefirst row Bayer array are connected to each other by the horizontalsignal line 404 (1, 2).

In the same way, the pixel electrodes 405 (2, 1), 405 (2, 3), 405 (2, 5)and 405 (2, 7) of the G pixels 400 (2, 1), 400 (2, 3), 400 (2, 5) and400 (2, 7) respectively which are laid out on the second row of thefirst row Bayer array are connected to each other by the horizontalsignal line 404 (1, 3). By the same token, the pixel electrodes 405 (2,2), 405 (2, 4), 405 (2, 6) and 405 (2, 8) of the B pixels 400 (2, 2),400 (2, 4), 400 (2, 6) and 400 (2, 8) respectively which are laid out onthe second row of the first row Bayer array are connected to each otherby the horizontal signal line 404 (1, 4).

In the same way, the pixel electrodes 405 (3, 1), 405 (3, 3), 405 (3, 5)and 405 (3, 7) of the G pixels 400 (3, 1), 400 (3, 3), 400 (3, 5) and400 (3, 7) respectively which are laid out on the first row of thesecond row Bayer array are connected to each other by the horizontalsignal line 404 (2, 1). By the same token, the pixel electrodes 405 (3,2), 405 (3, 4), 405 (3, 6) and 405 (3, 8) of the R pixels 400 (3, 2),400 (3, 4), 400 (3, 6) and 400 (3, 8) respectively which are laid out onthe first row of the second row Bayer array are connected to each otherby the horizontal signal line 404 (2, 2).

In the same way, the pixel electrodes 405 (4, 1), 405 (4, 3), 405 (4, 5)and 405 (4, 7) of the B pixels 400 (4, 1), 400 (4, 3), 400 (4, 5) and400 (4, 7) respectively which are laid out on the second row of thesecond row Bayer array are connected to each other by the horizontalsignal line 404 (2, 3). By the same token, the pixel electrodes 405 (4,2), 405 (4, 4), 405 (4, 6) and 405 (4, 8) of the G pixels 400 (4, 2),400 (4, 4), 400 (4, 6) and 400 (4, 8) respectively which are laid out onthe second row of the second row Bayer array are connected to each otherby the horizontal signal line 404 (2, 4).

The relations between the pixel electrodes 405 of pixels 400 and thehorizontal signal lines 404 are explained by again referring to thediagrams of FIGS. 14 and 15 as follows.

Let attention be paid to the Bayer array 401 (1, 1). The pixel electrode405 (1, 1) of the R pixel 400 (1, 1) is placed on the lower side in theR pixel 400 (1, 1) whereas the pixel electrode 405 (1, 2) of the G pixel400 (1, 2) adjacent to the R pixel 400 (1, 1) in the row direction isplaced on the upper side in the G pixel 400 (1, 2). By the same token,the pixel electrode 405 (2, 1) of the G pixel 400 (2, 1) is placed onthe lower side in the G pixel 400 (2, 1) whereas the pixel electrode 405(2, 2) of the B pixel 400 (2, 2) adjacent to the G pixel 400 (2, 1) inthe row direction is placed on the upper side in the B pixel 400 (2, 2).

That is to say, the pixel electrode 405 of any specific pixel 400 in aBayer array 401 is placed on a side opposite to the side in the pixelelectrode 405 of another pixel 400 adjacent to the specific pixel 400 inthe row direction in same Bayer array 401. In addition, the pixelelectrode 405 of any specific pixel 400 in a Bayer array 401 isconnected to a horizontal signal line 404 different from a horizontalsignal line 404 connected to the pixel electrode 405 of another pixel400 adjacent to the specific pixel 400 in the row direction in sameBayer array 401.

Let attention be paid to the Bayer array 401 (1, 1). The pixel electrode405 (1, 1) of the R pixel 400 (1, 1) is placed on the lower side in theR pixel 400 (1, 1) and the pixel electrode 405 (1, 2) of the G pixel 400(2, 1) adjacent to the R pixel 400 (1, 1) in the column direction isplaced also on the lower side in the G pixel 400 (2, 1). By the sametoken, the pixel electrode 405 (1, 2) of the G pixel 400 (1, 2) isplaced on the upper side in the G pixel 400 (1, 2) and the pixelelectrode 405 (2, 2) of the B pixel 400 (2, 2) adjacent to the G pixel400 (1, 2) in the column direction is placed also on the upper side inthe B pixel 400 (2, 2).

That is to say, the pixel electrode 405 of any specific pixel 400 in aBayer array 401 is placed on the same side as the pixel electrode 405 ofanother pixel 400 adjacent to the specific pixel 400 in the columndirection in the same Bayer array 401. In addition, the pixel electrode405 of any specific pixel 400 in a Bayer array 401 is connected to ahorizontal signal line 404 different from a horizontal signal line 404connected to the pixel electrode 405 of another pixel 400 adjacent tothe specific pixel 400 in the column direction in the same Bayer array401.

The relations between the location of the pixel electrode 405 of anyspecific pixel 400 in a Bayer array 401 and the location of the pixelelectrode 405 of another pixel 400 adjacent to the specific pixel 400 inthe column and row directions in the same Bayer array 401 have beendescribed above.

The following description explains a relation between the location ofthe pixel electrode 405 of a specific pixel 400 in a specific Bayerarray 401 and the location of the pixel electrode 405 of another pixel400 included in another Bayer array 401 adjacent to the specific Bayerarray 401 in the row direction to serve as another pixel 400 adjacent tothe specific pixel 400 in the row direction. Let the Bayer arrays 401(1, 1) and 401 (1, 2) be taken as an example of Bayer arrays adjacent toeach other in the row direction. The pixel electrode 405 (1, 2) of the Gpixel 400 (1, 2) in the Bayer array 401 (1, 1) is placed on the upperside in the G pixel 400 (1, 2) whereas the pixel electrode 405 (1, 3) ofthe R pixel 400 (1, 3) included in the Bayer array 401 (1, 2) adjacentto the Bayer array 401 (1, 1) in the row direction to serve as an Rpixel 400 adjacent to the G pixel 400 (1, 2) in the row direction isplaced on the lower side in the R pixel 400 (1, 3).

By the same token, the pixel electrode 405 (2, 2) of the B pixel 400 (2,2) in the Bayer array 401 (1, 1) is placed on the upper side in the Bpixel 400 (2, 2) whereas the pixel electrode 405 (2, 3) of the G pixel400 (2, 3) included in the Bayer array 401 (1, 2) adjacent to the Bayerarray 401 (1, 1) in the row direction to serve as a G pixel 400 adjacentto the B pixel 400 (2, 2) in the row direction is placed on the lowerside in the R pixel 400 (2, 3).

As described above, the pixel electrode 405 of a specific pixel 400 in aspecific Bayer array 401 is placed on a side opposite to the location ofthe pixel electrode 405 of another pixel 400 included in another Bayerarray 401 adjacent to the specific Bayer array 401 in the row directionto serve as another pixel 400 adjacent to the specific pixel 400 in therow direction. In addition, the pixel electrode 405 of a specific pixel400 in a specific Bayer array 401 is connected to a horizontal signalline 404 different from the horizontal signal line 404 connected to thelocation of the pixel electrode 405 of another pixel 400 included inanother Bayer array 401 adjacent to the specific Bayer array 401 in therow direction to serve as another pixel 400 adjacent to the specificpixel 400 in the row direction.

The following description explains a relation between the location ofthe pixel electrode 405 of a specific pixel 400 in a specific Bayerarray 401 and the location of the pixel electrode 405 of another pixel400 included in another Bayer array 401 adjacent to the specific Bayerarray 401 in the column direction to serve as another pixel 400 adjacentto the specific pixel 400 in the column direction. Let the Bayer arrays401 (1, 1) and 401 (2, 1) be taken as an example of Bayer arraysadjacent to each other in the column direction. Even though thelocations of the Bayer arrays 401 (1, 1) and 401 (2, 1) are separatedaway from each other by a distance equal to half the size of the Bayerarray, the locations of the Bayer arrays 401 (1, 1) and 401 (2, 1) areseparated away from each other in the column direction. Thus, the Bayerarrays 401 (1, 1) and 401 (2, 1) are taken as an example of adjacentBayer arrays.

The locations of the pixel electrodes 405 of the pixels 400 in the Bayerarray 401 (1, 1) are the mirror image of the locations of the pixelelectrodes 405 of the pixels 400 in the Bayer array 401 (2, 1).

To put it more concretely, the pixel electrode 405 (1, 1) of the R pixel400 (1, 1) on the left lower side in the Bayer array 401 (1, 1) isplaced on the lower side in the R pixel 400 (1, 1) whereas the pixelelectrode 405 (3, 1) of the G pixel 400 (3, 1) on the left upper side inthe Bayer array 401 (2, 1) is placed on the upper side in the G pixel400 (3, 1).

The pixel electrode 405 (1, 2) of the G pixel 400 (1, 2) on the rightlower side in the Bayer array 401 (1, 1) is placed on the upper side inthe G pixel 400 (1, 2) whereas the pixel electrode 405 (3, 2) of the Rpixel 400 (3, 2) on the right lower side in the Bayer array 401 (2, 1)is placed on the lower side in the R pixel 400 (3, 2).

The pixel electrode 405 (2, 1) of the G pixel 400 (2, 1) on the leftupper side in the Bayer array 401 (1, 1) is placed on the lower side inthe G pixel 400 (2, 1) whereas the pixel electrode 405 (4, 1) of the Bpixel 400 (4, 1) on the left upper side in the Bayer array 401 (2, 1) isplaced on the upper side in the B pixel 400 (4, 1).

The pixel electrode 405 (2, 2) of the B pixel 400 (2, 2) on the rightupper side in the Bayer array 401 (1, 1) is placed on the upper side inthe B pixel 400 (2, 2) whereas the pixel electrode 405 (4, 2) of the Gpixel 400 (4, 2) on the right upper side in the Bayer array 401 (2, 1)is placed on the lower side in the R pixel 400 (4, 2).

As described above, any specific pixel 400 of a specific Bayer array 401is placed on a side opposite to the side on which a counterpart pixel400 is included in a Bayer array 401 adjacent to the specific Bayerarray 401 in the column direction to serve as the counterpart to thespecific pixel 400.

The pixel electrode 405 of every pixel 400 is placed at a location andconnected to a horizontal signal line 404 as described above. Thefollowing description explains an operation to read out a pixel signalfrom the image sensor shown in the diagram of FIG. 15 or 16.

FIG. 17 is an explanatory circuit diagram referred to in description ofa read operation carried out in an all-pixel read mode. First of all, ahorizontal signal line 404 (r, 1) is selected and a pixel signal is readout from every pixel 400 connected to the horizontal signal line 404 (r,1). In the typical circuit diagram of FIG. 17, subscript r of notation404 (r, 1) denoting a horizontal signal line has a value of 1 or 2. Thatis to say, the horizontal signal line 404 (r, 1) is the horizontalsignal line 404 (1, 1) or the horizontal signal line 404 (2, 1).Notation r having such values is used in the following description.

When the horizontal signal line 404 (r, 1) is selected, the pixel signalof the R pixel 400 (1, 1) is read out from a vertical signal line 403-1,the pixel signal of the R pixel 400 (3, 2) is read out from a verticalsignal line 403-2, the pixel signal of the R pixel 400 (1, 3) is readout from a vertical signal line 403-3, the pixel signal of the R pixel400 (3, 4) is read out from a vertical signal line 403-4, the pixelsignal of the R pixel 400 (1, 5) is read out from a vertical signal line403-5, the pixel signal of the R pixel 400 (3, 6) is read out from avertical signal line 403-6 and the pixel signal of the R pixel 400 (1,7) is read out from a vertical signal line 403-7. That is to say, inthis case, when the horizontal signal line 404 (r, 1) is selected, apixel signal of an R pixel 400 is read out from every Bayer array.

Next, when the horizontal signal line 404 (r, 2) is selected, the pixelsignal of the G pixel 400 (1, 2) is read out from the vertical signalline 403-1, the pixel signal of the G pixel 400 (3, 1) is read out fromthe vertical signal line 403-2, the pixel signal of the G pixel 400 (1,4) is read out from the vertical signal line 403-3, the pixel signal ofthe G pixel 400 (3, 3) is read out from the vertical signal line 403-4,the pixel signal of the G pixel 400 (1, 6) is read out from the verticalsignal line 403-5, the pixel signal of the G pixel 400 (3, 5) is readout from the vertical signal line 403-6 and the pixel signal of the Gpixel 400 (1, 8) is read out from the vertical signal line 403-7. Thatis to say, in this case, when the horizontal signal line 404 (r, 2) isselected, a pixel signal of a G1 pixel 400 is read out from every Bayerarray.

Next, when the horizontal signal line 404 (r, 3) is selected, the pixelsignal of the G pixel 400 (2, 1) is read out from the vertical signalline 403-1, the pixel signal of the G pixel 400 (4, 2) is read out fromthe vertical signal line 403-2, the pixel signal of the G pixel 400 (2,3) is read out from the vertical signal line 403-3, the pixel signal ofthe G pixel 400 (4, 4) is read out from the vertical signal line 403-4,the pixel signal of the G pixel 400 (2, 5) is read out from the verticalsignal line 403-5, the pixel signal of the G pixel 400 (4, 6) is readout from the vertical signal line 403-6 and the pixel signal of the Gpixel 400 (2, 7) is read out from the vertical signal line 403-7. Thatis to say, in this case, when the horizontal signal line 404 (r, 3) isselected, a pixel signal of a G2 pixel 400 is read out from every Bayerarray.

Next, when the horizontal signal line 404 (r, 4) is selected, the pixelsignal of the B pixel 400 (2, 2) is read out from the vertical signalline 403-1, the pixel signal of the B pixel 400 (4, 1) is read out fromthe vertical signal line 403-2, the pixel signal of the B pixel 400 (2,4) is read out from the vertical signal line 403-3, the pixel signal ofthe B pixel 400 (4, 3) is read out from the vertical signal line 403-4,the pixel signal of the B pixel 400 (2, 6) is read out from the verticalsignal line 403-5, the pixel signal of the B pixel 400 (4, 5) is readout from the vertical signal line 403-6 and the pixel signal of the Bpixel 400 (2, 8) is read out from the vertical signal line 403-7. Thatis to say, in this case, when the horizontal signal line 404 (r, 4) isselected, a pixel signal of a B pixel 400 is read out from every Bayerarray.

By sequentially selecting a horizontal signal line among the horizontalsignal line 404 (r, 1), the horizontal signal line 404 (r, 2), thehorizontal signal line 404 (r, 3) and the horizontal signal line 404 (r,4), the pixel signals of the R, G1, G2 and B pixels composing 1 Bayerarray can be read out sequentially. That is to say, in this case, in 4horizontal scan operations, the read operation can be carried out.

By referring to a diagram of FIG. 18, the following description explainsread operations carried out in a thinned-out read mode.

In the first read operation carried out in a thinned-out read mode, thehorizontal signal line 404 (r, 4) used as the fourth horizontal signalline is selected for a Bayer array denoted by a notation including anodd column number whereas the horizontal signal line 404 (r, 2) used asthe second horizontal signal line is selected for a Bayer array denotedby a notation including an even column number. In the typical exampleshown in the diagram of FIG. 18, Bayer arrays each denoted by a notationincluding an odd column number are the Bayer array 401 (1, 1), the Bayerarray 401 (1, 2), the Bayer array 401 (1, 3) and the Bayer array 401 (1,4) whereas Bayer arrays each denoted by a notation including an evencolumn number are the Bayer array 401 (2, 1), the Bayer array 401 (2, 2)and the Bayer array 401 (2, 3).

By selecting the horizontal signal line 404 (r, 4) and the horizontalsignal line 404 (r, 2), the pixel signal of the B pixel 400 (2, 2) isread out from the vertical signal line 403-1, the pixel signal of the Gpixel 400 (3, 1) is read out from the vertical signal line 403-2, nopixel signals are read out from the vertical signal lines 403-3 and403-4, the pixel signal of the B pixel 400 (2, 6) is read out from thevertical signal line 403-5, the pixel signal of the G pixel 400 (3, 5)is read out from the vertical signal line 403-6 and no pixel signal isread out from the vertical signal line 403-7.

That is to say, in this case, by selecting the horizontal signal line404 (r, 4), the pixel signal of every B pixel 400 is read out from everyBayer array denoted by a notation including an odd column number and, byselecting the horizontal signal line 404 (r, 2), the pixel signal ofevery G1 pixel 400 is read out from every Bayer array denoted by anotation including an even column number. In addition, no pixel signalis read out from a vertical signal line 403 not demanded in formation ofa new Bayer array 401.

In the second read operation carried out in a thinned-out read mode, thehorizontal signal line 404 (r, 3) used as the third horizontal signalline is selected for a Bayer array denoted by a notation including anodd column number whereas the horizontal signal line 404 (r, 1) used asthe first horizontal signal line is selected for a Bayer array denotedby a notation including an even column number.

By selecting the horizontal signal line 404 (r, 3) and the horizontalsignal line 404 (r, 1), no pixel signal is read out from the verticalsignal line 403-1, the pixel signal of the R pixel 400 (3, 2) is readout from the vertical signal line 403-2, the pixel signal of the G pixel400 (2, 3) is read out from the vertical signal line 403-3, no pixelsignal is read out from the vertical signal lines 403-4 and 403-5, thepixel signal of the R pixel 400 (3, 6) is read out from the verticalsignal line 403-6 and the pixel signal of the G pixel 400 (2, 7) is readout from the vertical signal line 403-7.

That is to say, in this case, by selecting the horizontal signal line404 (r, 3), the pixel signal of every G2 pixel 400 is read out fromevery Bayer array denoted by a notation including an odd column numberand, by selecting the horizontal signal line 404 (r, 1), the pixelsignal of every R pixel 400 is read out from every Bayer array denotedby a notation including an even column number. In addition, no pixelsignal is read out from a vertical signal line 403 not demanded information of a new Bayer array 401.

As described above, by carrying out two scan operations, the pixelsignals of an R pixel 400, a G1 pixel 400, a G2 pixel 400 and a B pixel400 which form a new Bayer array 401 are each read out. That is to say,in this case, the pixels forming the new Bayer array 401 are a pixel 400(3, 2) serving as the R pixel, a G pixel 400 (3, 1) serving as the G1pixel, a G pixel 400 (2, 3) serving as the G2 pixel and a pixel 400 (2,2) serving as the B pixel. By the same token, in this case, a pixel 400(3, 6) serving as the R pixel, a G pixel 400 (3, 5) serving as the G1pixel, a G pixel 400 (2, 7) serving as the G2 pixel and a pixel 400 (2,6) serving as the B pixel also form a new Bayer array 401.

As described above, in a read operation carried out in thinned-out readmode, a horizontal signal line 404 selected for a Bayer array 401denoted by a notation including an odd column number is different from ahorizontal signal line 404 selected for a Bayer array 401 denoted by anotation including an even column number so that, by selecting avertical signal line 403 for reading out the pixel signal of a desiredpixel 400, the pixel signals of the four pixels composing a Bayer array401 can be read out in 2 read operations.

This read processing can be carried out half the number of timesdemanded in the past by the existing image sensor as for exampleexplained before by referring to the diagram of FIG. 5B.

In the typical example shown in the diagram of FIG. 18, the horizontalsignal lines 404 (r, 3) and (r, 4) are used as horizontal signal linesfor a Bayer array 401 denoted by a notation including an odd columnnumber whereas the horizontal signal lines 404 (r, 1) and (r, 2) areused as horizontal signal lines for a Bayer array 401 denoted by anotation including an even column number. It is to be noted, however,that combinations of the horizontal signal lines 404 bare by no meanslimited to this example. That is to say, other combinations of thehorizontal signal lines 404 are also possible. In addition, even in thecase of another combination, 2 read operations in the thinned-out readmode are carried out in the same way as what is described above.

It is to be noted that, in the embodiments described above, a Bayerarray has 4 pixels, i. e., an R (red color) pixel, a G1 (first greencolor) pixel, a G2 (second green color) pixel and a B (blue color)pixel. However, a complementary-color pixel can also be used.

By adopting the pixel-electrode layouts described above and making useof the read method explained above, horizontal signal lines areconnected to pixels as lines for selecting some of the pixels in a waythat varies from row to row. In addition, by connecting the horizontalsignal lines to the pixels in a way that varies from row to row, pixelseach serving as a subject of the read operation can also be changed fromrow to row. Thus, the speed of the read operation carried out in thethinned-out read mode can be made high in comparison with the speed forthe existing connection method. For example, the speed of the readoperation carried out in the thinned-out read mode can be made at leasttwice the speed for the existing connection method.

In addition, in the vertical and horizontal directions, following the ½thinned-out process, a new Bayer array crossing the border between Bayerarrays existing prior to the ½ thinned-out process can be created.

On top of that, by changing the read operation order of the horizontalsignal lines, the ½ thinned-out read mode can be applied only in thevertical direction.

In addition, by implementing the pixel sharing in a honeycomb state, thenumber of vertical signal lines can be doubled. With such anarrangement, each of the pixel thinned-out read operation and theaddition (in both the horizontal and vertical directions) can be carriedout at a high speed.

On top of that, in the case of read operations carried out in thethinned-out read mode, the number of read operations can be reduced.Thus, the amount of power demanded in the read operations can bedecreased. As a result, the power consumption of the entire imageprocessing apparatus can be reduced.

In addition, the image processing apparatus can be switched from aprocess to another with ease. Typical examples of the process are a readoperation carried out in an all-pixel read mode, a pixel additionprocess and a read operation carried out in a thinned-out read mode.

The embodiments described above can also be applied to a Bayer arraysystem rotated by 45 degrees. Also in the case of a Bayer array systemrotated by 45 degrees, by applying the present embodiment, the sameeffects as those described previously can be expected.

As described above, the image processing apparatus serving as an imagesensor provided by the present embodiment is that pixel electrodes ofpixels employed in the sensor are laid out in accordance with a layouttechnique peculiar to the sensor and connected to horizontal signallines also in accordance with a connection technique peculiar to thesensor. A manufacturing apparatus for manufacturing an image sensorhaving such characteristics is also included in a range to which thepresent invention can be applied.

To put it more concretely, the image sensor has a plurality of Bayerarrays each including 4 pixels sharing a common electrode connected to avertical signal line. Each of the 4 pixels composing a Bayer array isprovided with a pixel electrode which is connected to a horizontalsignal line. The locations of pixel electrodes each connected to ahorizontal signal line in any specific Bayer array are a mirror image ofthe locations of pixel electrodes each connected to a horizontal signalline in another Bayer array adjacent to the specific Bayer array. Amanufacturing apparatus for manufacturing an image sensor having suchcharacteristics is also included in the range of the present invention.

It is to be noted that implementations of the present invention are byno means limited to the embodiments described above. That is to say, theembodiments can be changed to a variety of modified versions within arange not deviating from essentials of the present invention.

In addition, it should be understood by those skilled in the art that avariety of modifications, combinations, sub-combinations and alterationsmay occur, depending on design demands and other factors insofar as theyare within the scope of the appended claims or the equivalents thereof.

What is claimed is:
 1. An imaging device, comprising: first, second,third, and fourth photodiodes; a first floating diffusion coupled to andreceiving electric charge from the first, second, third, and fourthphotodiodes; fifth, sixth, seventh, and eighth photodiodes; a secondfloating diffusion coupled to and receiving electric charge from thefifth, sixth, seventh, and eighth photodiodes; a first signal linecoupled to the first and sixth photodiodes; a second signal line coupledto the second and fifth photodiodes; a third signal line coupled to thethird and eighth photodiodes; and a fourth signal line coupled to thefourth and seventh photodiodes, wherein the first, second, fifth, andsixth photodiodes are arranged in this order in a first row ofphotodiodes, and wherein the second signal line transfers electriccharge for the second and fifth photodiodes.
 2. The imaging device ofclaim 1, wherein the third, fourth, seventh, and eighth photodiodes arearranged in this order in a second row of photodiodes.
 3. The imagingdevice of claim 1, wherein the first photodiode is adjacent the thirdphotodiode in a vertical direction.
 4. The imaging device of claim 1,wherein the first, second, third, and fourth photodiodes are coupled tothe first floating diffusion via first, second, third, and fourthtransfer transistors, respectively, and wherein the fifth, sixth,seventh, and eighth photodiodes are coupled to the second floatingdiffusion via fifth, sixth, seventh, and eighth transfer transistors,respectively.
 5. The imaging device of claim 4, wherein the first signalline is coupled to gates of the first and sixth transfer transistors,wherein the second signal line is coupled to gates of the second andfifth transfer transistors, wherein the third signal line is coupled togates of the third and eighth transfer transistors, and wherein thefourth signal line is coupled to gates of the fourth and seventhtransfer transistors.
 6. The imaging device of claim 1, wherein thefirst, second, third, and fourth photodiodes are arranged in a first 2×2array, and wherein the first floating diffusion is located at a centerof the first 2×2 array.
 7. The imaging device of claim 6, wherein thefifth, sixth, seventh, and eighth photodiodes are arranged in a second2×2 array, wherein the second floating diffusion is located at a centerof the second 2×2 array.
 8. The imaging device of claim 7, wherein thefirst, second, third, and fourth signal lines are horizontal signallines, wherein the first floating diffusion is connected to a firstvertical signal line, and wherein the second floating diffusion isconnected to a second vertical signal line.
 9. The imaging device ofclaim 8, wherein the first floating diffusion is connected to the firstvertical signal line by a first common electrode, and wherein the secondfloating diffusion is connected to the second vertical signal line by asecond common electrode.
 10. The imaging device of claim 1, whereinfirst, fourth, fifth, and eighth photodiodes are included in greenpixels.
 11. The imaging device of claim 10, wherein the second and sixthphotodiodes are included in blue pixels, and wherein the third andseventh photodiodes are included in red pixels.
 12. The imaging deviceof claim 1, wherein, in the plan view, the first and fourth signal linesare between the second and third signal lines.
 13. The imaging device ofclaim 1, wherein the first signal line transfers electric charge for thefirst and sixth photodiodes, wherein the second signal line transferselectric charge for the second and fifth photodiodes, wherein the thirdsignal line transfers electric charge for the third and eighthphotodiodes, and wherein the fourth signal line transfers electriccharge for the fourth and seventh photodiodes.
 14. The imaging device ofclaim 13, wherein the first signal line controls transfer of electriccharge for the first photodiode to the first floating diffusion andcontrols transfer of electric charge for the sixth photodiode to thesecond floating diffusion, wherein the second signal line controlstransfer of electric charge for the second photodiode to the firstfloating diffusion and controls transfer of electric charge for thefifth photodiode to the second floating diffusion, wherein the thirdsignal line controls transfer of electric charge for the thirdphotodiode to the first floating diffusion and controls transfer ofelectric charge for the eighth photodiode to the second floatingdiffusion, and wherein the fourth signal line controls transfer ofelectric charge for the fourth photodiode to the first floatingdiffusion and controls transfer of electric charge for the seventhphotodiode to the second floating diffusion.